Key players in Congress -– Republicans and Democrats -- are skeptical of the Iran deal and want to see the fine print. 
 
 No one is ruling out a big push ahead on new Iran sanctions, or a measure to require President Obama to get congressional approval, two pieces of legislation the White House strongly opposes. 
 
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 But there appears to be a willingness to hear the administration out in promised briefings on the framework when lawmakers return to Washington on April 13. 
 
 An aide to House Speaker John Boehner tells ABC News that the approach in the House is not a “wait-and-see until June 30th” posture, but that Republicans want the briefings, a chance to review the details and discuss possible next steps with members. 
 
 Sen. Bob Corker, chairman of the Senate Foreign Relations Committee, said today “it is important that we wait to see the specific details of today’s announcement” and that everyone “must remain clear-eyed.” He vowed an April 14 committee vote on a bill to require congressional review of a nuclear deal, but there is no plan yet to bring it up for a vote in the full chamber. (Corker has said he’d like to have a veto-proof majority before the bill is voted on by the full Senate.) 
 
 “We’ll know more in the days ahead, after April 14,” an aide to Senate Majority Leader Mitch McConnell told ABC News. 
 
 Rep. Adam Schiff, the top Democrat on the House Intelligence Committee, said he was surprised so many details were revealed in the framework and said that Congress should “be careful not to scuttle the opportunity for a diplomatic resolution. 
 
 “I think there is sufficient detail that has been arrived at these negotiations that Congress needs to be careful not to scuttle the opportunity for a diplomatic resolution,” Schiff said in an interview. “The last thing we want is for the international community to think that we came this close to a negotiated end to Iran’s nuclear program and the United States Congress got in the way.” 
 
 Sen. Tom Cotton, R-Arkansas, the author of the controversial open letter to Iran's leaders signed by 47 Republican senators, called the interim deal a "list of very dangerous U.S. concessions that will put Iran on the path to a nuclear weapon." 
 
 “I plan to work with all of my colleagues on both sides of the aisle who have already expressed disquiet about terms such as these, to stop this deal from going forward, to keep America safe, and to prevent a nuclear arms race in the Middle East,” he added. 
 
 Sen. Marco Rubio, R-Florida, who is likely weeks away from announcing a presidential bid, tweeted his skepticism of the deal, but said he is awaiting more information. 
 
 Awaiting more details on #Iran deal but early reports indicate this is Obama admin spinning diplomatic failure. — Marco Rubio (@marcorubio) April 2, 2015 
 
 The White House fired another warning shot this afternoon reiterating veto threats for any legislation that “undercuts our ability to get the deal done.” 
 
 “We think it’s best for members of Congress to take a look at the framework and then give the space to look at final details between now and June,” said deputy national security adviser Ben Rhodes. 
 
 Congress needs to “wait and see what the deal is, and then we can determine the best way to support Congress playing an oversight role,” he said. ||||| For the Obama administration, its critics in Congress and even for the Iranians, the psychology and tactics of setting deadlines have changed drastically over the past year. 
 
 Earlier this year, congressional Republicans pressed for a firm date for coming up with an agreement, warning they were ready to respond to a negotiating failure by imposing tougher sanctions on Iran. 
 
 Then it became clear that the deadlines were helping Tehran more than they were helping Washington. The Iranians seemed to be holding out on critical issues in the hopes that the United States would yield in the final hours. 
 
 So Senator Bob Corker, the Tennessee Republican and chairman of the Senate Foreign Relations Committee, who sponsored the law that now requires the White House to send any agreement to Congress for approval, began urging patience. 
 
 Obama administration officials argue that deadlines would push all sides, but especially the Iranians, whose opaque political system make it difficult to reach the decisions needed to seal any nuclear accord. 
 
 Yet administration officials have also been willing to interpret the deadlines somewhat liberally. At an early round of talks in Lausanne, Switzerland, American negotiators opted to put another couple of days on the clock in early April rather than return home empty-handed. 
 
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 The Iranians have insisted that meeting deadlines did not enter into their calculations. “We do not see any definite deadline as to our work here,” a senior Iranian official told reporters here on Monday. 
 
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 No deadline, perhaps, but plenty of urgency. The chief Iranian negotiator, Mohammad Javad Zarif, knows he will be measured at home by the details of the deal, but also by the speed with which sanctions on oil sales and financial transactions begin to be lifted. 
 
 The fixation all sides have on time, after 20 months, has been exacerbated in part by soaring temperatures in Vienna, overwhelming the air-conditioning systems of a city that is long accustomed to heated negotiations, though not to actual heat. 
 
 To sustain itself during its marathon meetings, the United States negotiating team has since the beginning of June consumed at least 10 pounds of Twizzlers, 30 pounds of mixed nuts and dried fruit, 20 pounds of string cheese and more than 200 Rice Krispie Treats, according to its informal count. 
 
 At a briefing Tuesday, a senior administration official suggested that progress had been made on some long-running issues, including access to military sites by inspectors. The answer lay in guaranteeing what is known as “managed access” for inspectors working for the International Atomic Energy Agency. The term refers to an elaborate set of procedures that allow a country to shield conventional, secret military facilities while still allowing the agency’s inspectors to look for evidence of nuclear activity. How that would be established under an agreement with the Iranians, and how any disputes over managed access would be resolved, remained unclear. 
 
 Similarly, the official, who briefed reporters on the condition of anonymity, declined to say whether the scope and sophistication of Iran’s longer-range research and development program to design far faster, more efficient centrifuges to enrich uranium would ultimately be made public. Unless that information was made available in some form, it would be difficult to assess to what extent an accord slows Iran’s longer-term nuclear ambitions. 
 
 And there have been continuing arguments over the shape of a new United Nations Security Council resolution on Iran that would replace several existing resolutions that impose sanctions on the country’s import and export of conventional arms. American officials said there was agreement in Lausanne three months ago that the arms embargo would continue under any new resolution. 
 
 In Washington on Tuesday, Gen. Martin E. Dempsey, who is coming to the end of his term as chairman of the Joint Chiefs of Staff, bluntly told Congress that “under no circumstances should we relieve pressure on Iran relative to ballistic missile capabilities and arms trafficking.” 
 
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 Yet Iran is pushing heavily to ease or remove the restrictions, possibly with support from Russia, which may want to sell arms to Tehran. Sergei V. Lavrov, Russia’s foreign minister, said Tuesday that the United Nations ban on missile and arms sales to Iran was still a “big problem” in the talks. 
 
 Administration officials still hoped to conclude the talks by Thursday — though that is not a deadline — so the agreement could be submitted to Congress for a 30-day review. That review period would double if the agreement were completed later this summer. 
 
 The White House has sought to rebut Republican charges that it has been rushing to finish the agreement in order to limit the time congressional critics might have to mobilize opposition to an accord. “The president’s ready to call the team home” if American objectives cannot be met, Josh Earnest, the White House press secretary said. 
 
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 But the Obama administration is not at that point yet. The first sign the talks would be extended came when a sign was posted in the lobby of a four-star hotel notifying members of the United States delegation who are staying there that they needed new room keys because their reservations had been extended. (The new reservation, a hotel clerk said, is until Saturday.) ||||| WASHINGTON — Leading lawmakers from both parties in Congress responded cautiously on Thursday to the tentative framework for a nuclear deal between Western powers and Iran, demanding to review any final agreement but pointedly refraining from a vow to kill the accord. 
 
 Congress could still scuttle a deal if lawmakers move forward with tough new sanctions on Iran just as economic and nuclear penalties are supposed to be lifted. And Senator Bob Corker of Tennessee, the chairman of the Senate Foreign Relations Committee, said the panel would continue with plans to formally draft bipartisan legislation on April 14 insisting on congressional examination of any agreement. 
 
 The committee’s leadership was looking for ways to shape a bill that would gain broad approval in both parties. 
 
 “We want the right to go through the details of the deal and to decide whether we believe congressionally mandated sanctions should be alleviated,” Mr. Corker said in an interview. 
 
 That sentiment was bipartisan. 
 
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 “If Congress appears to be bypassed, that’s not good for the national debate and national unity as we move forward with Iran,” said Representative Eliot L. Engel of New York, the ranking Democrat on the Foreign Affairs Committee. 
 
 President Obama made a pointed appeal to Congress to let diplomacy work, even as he promised consultation. 
 
 “If Congress kills this deal — not based on expert analysis, and without offering any reasonable alternative — then it’s the United States that will be blamed for the failure of diplomacy,” he said at the White House. “International unity will collapse, and the path to conflict will widen.” 
 
 But a senior administration official hinted at compromise, at least on the review legislation. He reiterated the president’s promise to veto legislation imposing new sanctions on Iran, but said that a previous veto threat on the congressional review bill applied only to the measure as it was originally drafted. 
 
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 The jousting is likely to continue for months, and pressure could mount on Republican leaders to toughen their stand. Negotiators must turn a framework into a detailed agreement by this summer, and legal sanctions imposed by the United States will not have to be lifted anytime soon, possibly not for years. The agreement is not likely to require action from Congress until the next presidential administration. 
 
 But beyond the leadership suites, a more hard-edge response came quickly. 
 
 “The Obama administration’s efforts to get a deal at any cost will have a greater cost than the world can bear,” said Representative Michael McCaul of Texas, the chairman of the Homeland Security Committee. “If this deal moves forward, the consequences for the U.S. and our allies in the region will be dire.” 
 
 Some Democrats hailed it. “We’ve set the stage for a paradigm shift in the country and in the region,” said Representative Earl Blumenauer, Democrat of Oregon. 
 
 But other Democrats tried to find a middle ground between embracing the accord and undermining it. Senator Benjamin L. Cardin of Maryland, the ranking Democrat on the Foreign Relations Committee, said that he wanted unanimity around Congress’s request for review, and that aspects of the legislation would have to be toned down. 
 
 The bill demands that the administration submit the full text of any agreement to Congress, including classified annexes. It would prohibit the removal of any congressional sanctions for 60 days after a final accord, and would require the president to certify Iranian compliance every 90 days. Without that certification, it mandates a quick return of sanctions. 
 
 The original version was written by Mr. Corker and Senator Robert Menendez, Democrat of New Jersey, a hard-liner on the Iran talks. But Mr. Menendez’s indictment Wednesday on corruption charges, and his decision to step down from the top Democratic spot on the Foreign Relations Committee, elevated the more diplomatic voice of Mr. Cardin. 
 
 “The more unity we can have among Democrats and the White House, the stronger U.S. foreign policy will be,” Mr. Cardin said. 
 
 In general, the most senior Republicans, while cool to the deal, spoke in measured tones. “In the weeks ahead, Republicans and Democrats in Congress will continue to press this administration on the details of these parameters and the tough questions that remain unanswered,” said the House speaker, John A. Boehner of Ohio. “We will stand strong on behalf of the American people and everyone in the Middle East who values freedom, security and peace.” 
 
 The biggest question is not about the congressional review legislation but about whether Republican leaders will try to resurrect House and Senate measures that would impose tough new sanctions on Iran. Both versions have had broad bipartisan support, but their passage could imperil a final deal. 
 
 “There will be a move to apply new sanctions or deprive the president of the ability to waive existing sanctions,” said Representative Brad Sherman, Democrat of California and a senior member of the House Foreign Affairs Committee. While that inclination is present in both chambers and in both parties, he said, “the tendency will be to vote for or against the president based on party.” 
 
 Mr. Obama, announcing the tentative accord in the White House Rose Garden, said the issues at stake were “bigger than politics.” 
 
 “These are matters of war and peace, and they should be evaluated based on the facts and what is ultimately best for the American people and for our national security,” he said. 
 
 But lawmakers in both parties asked pointed questions about the framework presented. Mr. Corker said that he believed sanctions would be lifted too quickly, and that he wanted to better understand what would happen to Iran’s fissile nuclear materials. Mr. Engel was pleased that Iran’s array of centrifuges would be reduced by two-thirds, and that inspections of uranium mining and milling would last 25 years. 
 
 “But tell me why Fordo remains open,” he said, referring to Iran’s underground enrichment site. “Why not just destroy it?”
– A blueprint outlining the path toward a final deal between Western countries and Iran on its nuclear program was drafted yesterday, and Politico notes "there was much for Obama officials" and their partner countries to "be happy about," such as more centrifuge disassembling than previously anticipated. But there are still tenuous points that need to be fleshed out and an American public that needs convincing, and a congressional committee intends to create a bipartisan bill on April 14 that would demand congressional review of any deal, the New York Times notes. An aide for Speaker John Boehner tells ABC News that "a wait-and-see until June 30" (the deadline for a full agreement) approach isn't in the cards, while Sen. Bob Corker tells the Times "we want the right to go through the details of the deal and to decide whether we believe congressionally mandated sanctions should be alleviated." Keeping the agreement's framework shaky is the lack of detailed schedules and logistics on certain key points, including nuclear R&D and a uranium-reduction program, Politico notes. The bill would insist on a full review of all agreement text, ban the removal of sanctions for 60 days after a final deal is reached, and mandate that the president check up on Iran's compliance every 90 days, the Times notes. But while lawmakers on both sides are touting compromise, there are still the hardballers. "I plan … to stop this deal from going forward," Sen. Tom Cotton, author of the recent open letter to Iran, tells ABC. Meanwhile, Democrat Rep. Adam Schiff says, "The last thing we want is for the international community to think that we came this close to a negotiated end to Iran's nuclear program and the United States Congress got in the way."