The US has offered Russia an olive branch, saying it will delay activation of its proposed missile defence sites in Eastern Europe.
The US wants to deploy ten interceptor missiles in Poland and a radar station in the Czech Republic to counter possible attacks from countries such as Iran.
Russia says the plan is a threat to its own security and has responded with threats to target missiles at the EU if the US continues with its plans.
US Defence Secretary Robert Gates says the offer - the details of which have yet to be worked out - was raised in a meeting with Russian President Vladamir Putin in Moscow last week.
"We would consider tying together the activation of the sites in Poland and the Czech Republic with definitive proof of the threat, in other words, Iranian missile testing and so on," Gates says.
“We would develop the sites, build the sites, but perhaps we would delay activating them until there was concrete proof of the threat from Iran".
Russian officials says the proposal is not the solution they are looking for, but say it is a "positive signal" and clears the way for further negotiations.
By Elizabeth Clifford-Marsh