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. . . .

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. . . .

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.

Image: Acting Under Secretary of State for Arms Control and International Security Rose Gottemoeller (photo: Department of State)