TEHRAN (Reuters) - Iranian Supreme Leader Ayatollah Ali Khamenei told visiting Russian President Vladimir Putin on Wednesday that Tehran and Moscow must step up cooperation to isolate the United States and help stabilize the Middle East, state TV reported. Sputnik/Alexei Druzhinin/Kremlin via REUTERS 
 
 Iran and Russia are the main allies of Syrian President Bashar al-Assad, while the United States, Turkey and most Arab states support rebel groups fighting to overthrow him. (AP Photo/Ebrahim Noroozi) (Associated Press) 
 
 TEHRAN, Iran (AP) — Russian President Vladimir Putin on Wednesday strongly backed Iran and its nuclear deal with world powers, saying Moscow opposed "any unilateral change" to the accord after U.S. President Donald Trump refused to re-certify it. "Iranian and Russian cooperation has had a great impact in fighting terrorism in the region," Rouhani said, according to a statement from his office. RAPPROCHEMENT 
 
 The rapprochement between Iran and Russia is worrying for both Saudi Arabia, Shi’ite Muslim Tehran’s main Sunni rival for dominance in the Middle East, and the United States. Putin praised cooperation with Iran as “very productive”. "We oppose linking Iran's nuclear program with other issues including defensive issues." Moscow is also an important ally for Iran in its renewed confrontation with the United States, where Trump broke ranks with major allies on Oct. 13 by de-certifying Tehran’s nuclear deal with six world powers including Washington under his predecessor Barack Obama. Trump has called the nuclear agreement, which was reached under his predecessor Barack Obama, “the worst deal ever negotiated” and has adopted a harsh approach to Iran over its nuclear and ballistic missile programs. "We oppose any unilateral change in the multilateral nuclear deal," Putin said while meeting Khamenei, according to a statement from the supreme leader's office. The U.S. Congress now will make a decision regarding the 2015 nuclear deal, in which Iran agreed to limit its enrichment of uranium in exchange for the lifting of economic sanctions. These were lifted under the 2015 accord in return for Tehran curbing nuclear activity of potential use in developing an atomic bomb. "The joint cooperation and consultations are very important in the final stages too." Another Iranian official said Trump’s hawkish Iran policy had united the Islamic Republic’s often feuding leadership - split into hardline conservative, pragmatist and reformist factions - in alignment with Russia. Tehran-based political analyst Saeed Leilaz said Putin's visit to Tehran could lead to more investment in the oil industry and other infrastructure projects that "may encourage European and Chinese and even American companies to enter the Iranian market."
– After President Trump refused to recertify Iran's compliance with a 2015 nuclear deal, Ayatollah Ali Khamenei said it was a "waste [of] time to respond to the rants and whoppers of the foul-throated president of the United States." But the country's supreme leader had more to say in response Thursday, when he declared America "the number one enemy of our nation," Reuters reports. "The American president's foolish remarks against our people show the depth of America's hostility towards the entire Iranian nation," he said in a televised speech. "We will never accept their bullying over the nuclear deal ... Americans are using all the wickedness to damage the result of the nuclear talks." The US is the only one of the signatories of the multinational nuclear deal refusing to recertify, and the UN on Sunday confirmed Iran is still adhering to the deal, which lifted most sanctions in exchange for Tehran cutting back on its development of its nuclear program. The other signatories say even withdrawal by the US—which is up to Congress—would not cancel the international accord, but Iran has warned of consequences if the deal does crumble. "Any retreat by Iran will make America more blatant and impudent," Khamenei said Thursday. "Resistance is the only option." His speech comes a day after Russian President Vladimir Putin expressed support for the deal during a visit to Iran, the AP reports. Khamenei told Putin during that visit that Iran and Russia must work together toward Middle East stability and isolate the US, Reuters reports.