The US plans to put some weapons in storage rather than destroy them
The Russian Defence Minister, Sergei Ivanov, has announced plans to visit Washington next month, a day after the failure of the two sides to reach agreement on nuclear arms.
Following a meeting in Moscow on Tuesday, Russian and American delegations admitted that there were still what they described as "difficult issues" between them.
They said it may not be possible to sign an agreement on nuclear arms reduction when the US President, George Bush, goes to Russia in May.
Mr Ivanov might have expected to visit Washington as part of the preparation for Mr Bush's first trip to Russia. But Tuesday's lack of success has given his trip an added urgency.
Mounting questions
After the break-up of the talks on Tuesday evening, the two sides were trying to play down their differences, even suggesting that it wouldn't be too serious if the agreement were not ready for signing when the two presidents met in May.
But both Moscow and Washington know that the failure to sign a deal would be a set-back for their new relationship, forged after the attacks on the US on 11 September.
Indeed, a number of questions are already being asked about the strength of the Russia-US alliance.
The two countries may be united in the war against terrorism, but they seem as far apart as ever in other strategic matters.
Going it alone
Washington announced its intention unilaterally to pull out of the Anti-Ballistic Missile Treaty, despite Moscow's protests.
And while the Americans agree that it makes sense to reduce their nuclear warheads, they insist that they will put many of their undeployed warheads into storage, rather than destroy them - a prospect which has angered Moscow.
But the inability to reach an agreement this week suggests that, as with the ABM Treaty, Washington may end up simply doing what it wants.
Such a move will cause the hawks in Mr Putin's military to ask if there is any real gain for Moscow in this relationship.