The Bush administration's top arms control official says Moscow is hardening its stance against a proposed U.S. missile defense system in Europe - apparently intending to "test the mettle" of incoming President Obama on the issue. But State Department arms control chief John Rood is also optimistic the two powers can reach a new strategic arms limitation treaty next year.

The State Department's top arms control official says Moscow is showing little interest in new U.S. confidence-building proposals on European missile defense, apparently in the hope that the incoming Obama administration will drop the controversial program.

The Bush administration plans to deploy missile interceptors in Poland and a related radar system in the Czech Republic to counter what is seen as a looming long-range missile threat from Iran. But Moscow has strongly opposed it as a threat to its strategic deterrence.

Acting Undersecretary of State for Arms Control and International Security John Rood visited Moscow earlier this week to discuss a set of proposals to ease Russian concerns about the plan, including allowing Russian personnel to be stationed at the two facilities to monitor operations.

However, Rood told reporters the discussion on missile defense made no headway and that Russian officials were "less flexible" than before on U.S. confidence-building ideas. He said Moscow has apparently put discussions with Washington on hold until it determines the position of President-elect Obama, who has not endorsed the Bush administration plan.

"They have paused, I think with the election of a new administration in the United States and I think they are looking carefully at the position of the new team," said Rood. "My assessment is that the Russians intend to test the mettle [courage] of the new administration and the new president, and the future will show how the new administration chooses to answer that challenge."

Rood said the next administration can expect challenges by Moscow on missile defense and other areas, though he did not elaborate. Spokespersons for the president-elect have said he supports a missile defense shield only when "the technology is proved to be workable."

Rood's one-day Moscow visit also included discussion of a U.S. proposal conveyed to the Russian government in October on a new nuclear weapons accord to replace the Strategic Arms Limitation Treaty or START, which expires at the end of next year.

The U.S. proposal would limit the number of nuclear warheads on both sides as opposed to the much more intricate START treaty, which limits strategic weapon delivery systems such as bombers, submarines, and inter-continental missiles.

Acting Undersecretary Rood said Moscow also wants a new treaty to limit some conventional weapons systems on both sides, and gave his team a position paper with counter-proposals.

Though he said his mission yielded no agreements on the subject, he is optimistic a new weapons deal can be ready by the time the existing treaty expires.

"While there is a difference of opinion on START treaty particulars, there is not a difference of opinion on the objective," said Rood. "Both sides were very clear that we want to reach an agreement on a successor agreement for the START treaty before the expiration of the START treaty. The Russians stated, and they have shown, significant commitment to that objective. And I think on missile defense, they are committed to continuing a dialogue with the United States, or that's my impression."

Rood said Russian threats to target Poland and the Czech Republic with missiles because they are to host the U.S. defense system are regrettable and have no place in political discourse.

But he said both Poland, which he visited this week, and the Czech Republic are not disturbed by the Russian rhetoric and are confident about the NATO defense commitment to them.

He also said there is no particular concern in Washington about recent Russian military exercises with Venezuela, saying the dispatch of Cold War-era aircraft or Russian naval vessels to the Caribbean is "just not something that really causes the blood-pressure to rise here."