U.S. Says Russia Tested Missile, Despite Treaty WASHINGTON - The United States informed its NATO allies this month that Russia had tested a new ground-launched cruise missile, raising concerns about Moscow's compliance with a landmark arms control accord. American officials believe Russia began conducting flight tests of the missile as early as 2008. Such tests are prohibited by the treaty banning medium-range missiles that was signed in 1987 by President Ronald Reagan and Mikhail S. Gorbachev, the Soviet leader at the time, and that has long been viewed as one of the bedrock accords that brought an end to the Cold War. Beginning in May, Rose Gottemoeller, the State Department's senior arms control official, has repeatedly raised the missile tests with Russian officials, who have responded that they investigated the matter and consider the case to be closed. But Obama administration officials are not yet ready to formally declare the tests of the missile, which has not been deployed, to be a violation of the 1987 treaty. With President Obama pledging to seek deeper cuts in nuclear arms, the State Department has been trying to find a way to resolve the compliance issue, preserve the treaty and keep the door open to future arms control accords. "The United States never hesitates to raise treaty compliance concerns with Russia, and this issue is no exception," Jen Psaki, the State Department spokeswoman, said. There's an ongoing review process, and we wouldn't want to speculate or prejudge the outcome. Other officials, who asked not to be identified because they were discussing internal deliberations, said there was no question the missile tests ran counter to the treaty and the administration had already shown considerable patience with the Russians. And some members of Congress, who have been briefed on the tests on a classified basis for well over a year, have been pressing the White House for a firmer response. A public dispute over the tests could prove to be a major new irritant in the already difficult relationship between the United States and Russia. In recent months, that relationship has been strained by differences over how to end the fighting in Syria; the temporary asylum granted to Edward J. Snowden, the former National Security Agency contractor; and, most recently, the turmoil in Ukraine. The treaty banning the testing, production and possession of medium-range missiles has long been regarded as a major step toward curbing the American and Russian arms race. "The importance of this treaty transcends numbers," Mr. Reagan said during the treaty signing, adding that it underscored the value of "greater openness in military programs and forces." But after President Vladimir V. Putin rose to power and the Russian military began to re-evaluate its strategy, the Kremlin developed second thoughts about the accord. During the administration of President George W. Bush, Sergei B. Ivanov, the Russian defense minister, proposed that the two sides drop the treaty. Though the Cold War was over, he argued that Russia still faced threats from nations on its periphery, including China and potentially Pakistan. But the Bush administration was reluctant to terminate a treaty that NATO nations regarded as a cornerstone of arms control and whose abrogation would have enabled the Russians to increase missile forces directed at the United States" allies in Asia. Since Mr. Obama has been in office, the Russians have insisted they want to keep the agreement. But in the view of American analysts, Russia has also mounted a determined effort to strengthen its nuclear abilities to compensate for the weakness of its conventional, nonnuclear forces. At the same time, in his State of the Union address last year, Mr. Obama vowed to "seek further reductions in our nuclear arsenals," a goal American officials at one point hoped might form part of Mr. Obama's legacy. But administration officials and experts outside government say Congress is highly unlikely to approve an agreement mandating more cuts unless the question of Russian compliance with the medium-range treaty is resolved. "If the Russian government has made a considered decision to field a prohibited system," Franklin C. Miller, a former defense official at the White House and the Pentagon, said, "then it is the strongest indication to date that they are not interested in pursuing any arms control, at least through the remainder of President Obama's term." It took years for American intelligence to gather information on Russia's new missile system, but by the end of 2011, officials say it was clear that there was a compliance concern. There have been repeated rumors over the last year that Russia may have violated some of the provisions of the 1987 treaty. But the nature of that violation has not previously been disclosed, and some news reports have focused on the wrong system: a new two-stage missile called the RS-26. The Russians have flight-tested it at medium range, according to intelligence assessments, and the prevailing view among Western officials is that it is intended to help fill the gap in Russia's medium-range missile capabilities that resulted from the 1987 treaty. The treaty defines medium-range missiles as ground-launched ballistic or cruise missiles capable of flying 300 to 3,400 miles. But because Russia has conducted a small number of tests of the RS-26 at intercontinental range, it technically qualifies as a long-range system and will be counted under the treaty known as New Start, which was negotiated by the Obama administration. So it is generally considered by Western officials to be a circumvention, but not a violation, of the 1987 treaty One member of Congress who was said to have raised concerns that the suspected arms control violation might endanger future arms control efforts was John Kerry. As a senator and chairman of the Foreign Relations Committee, he received a classified briefing on the matter in November 2012 that dealt with compliance concerns, according to a report in The Daily Beast. As secretary of state, Mr. Kerry has not raised concerns over the cruise missile tests with his Russian counterpart, Sergey V. Lavrov, but he has emphasized the importance of complying with arms accords, a State Department official said. Republican lawmakers, however, have urged the administration to be more aggressive. "Briefings provided by your administration have agreed with our assessment that Russian actions are serious and troubling, but have failed to offer any assurance of any concrete action to address these Russian actions," Representative Howard McKeon, Republican of California and chairman of the Armed Services Committee, and Representative Mike Rogers, the Michigan Republican who leads the Intelligence Committee, said in an April letter to Mr. Obama. And Senator Jim Risch, Republican of Idaho, and 16 other Republican senators recently proposed legislation that would require the White House to report to Congress on what intelligence the United States has shared with NATO allies on suspected violations of the 1987 treaty. Republican members of the Senate Foreign Relations Committee have also cited the issue in holding up Ms. Gottemoeller's confirmation as under secretary of state for arms control and international security. It was against this backdrop that the so-called deputies committee, an interagency panel led by Antony Blinken, Mr. Obama's deputy national security adviser, decided that Ms. Gottemoeller should inform NATO's 28 members about the compliance issue. On Jan. 17, Ms. Gottemoeller discussed the missile tests in a closed-door meeting of NATO's Arms Control, Disarmament and Non-Proliferation Committee that she led in Brussels. The Obama administration, she said, had not given up on diplomacy. There are precedents for working out disputes over arms control complaints, and Ms. Gottemoeller said American officials would continue to engage the Russians to try to resolve the controversy. But even with the best of intentions, establishing what the Russians are doing may not be easy. The elaborate network of verification provisions created under the medium-range missile treaty is no longer in effect, since all the missiles that were believed to be covered by the agreement were long thought to have been destroyed by May 1991.