Negotiators from the United States and Russia on Tuesday resumed talks aimed at reaching a new nuclear arsenals reduction agreement to replace the 1991 START treaty, diplomatic sources said.

The talks were resumed at the U.S. diplomatic mission to the United Nations Office in Geneva. Like previous rounds of talks, negotiators were meeting behind closed doors and no news conferences were scheduled.

The two sides have been trying since last May to negotiate a new nuclear arms reduction deal as part of their efforts to "reset" relations between the two countries.

The new deal was supposed to replace the old START treaty (Strategic Arms Reduction Treaty), which was signed in 1991 and led to major reductions in the U.S. and Russian nuclear arsenals at the end of the Cold War.

But the negotiators had missed an original target to reach a new deal before the expiry of START, which was on Dec. 5, 2009.

According to Russian Foreign Minister Sergei Lavrov, "there are chances" that the negotiations could be concluded in two to three weeks.

But "there are no artificial deadlines," he told reporters in Moscow.