GENEVA (Reuters) -- Verification of missiles stocks and reduction is holding up agreement on a new U.S.-Russian arms deal, a senior diplomatic source said today.
The two powers failed to reach a deal on December 4 to replace a Cold War treaty to cut their nuclear arsenals as it expired but agreed the 1991 Strategic Arms Reduction Treaty (START) would remain in force as negotiators continued to work.
"The Russians want a less intrusive system than the old treaty," said the source, who is not involved in the negotiations but is informed of their progress.
The expiry of the old START agreement has already led to the withdrawal of U.S. monitors from a Russian site in Votkinsk, U.S. State Department spokesman Ian Kelly said on December 4.
The talks have been taking place in Geneva for several months.
Presidents Barack Obama and Dmitry Medvedev issued a joint statement on December 4 saying they were determined to work for a new pact at the earliest possible date.
There has been speculation that a deal -- if completed in time -- could be signed in the coming weeks while Obama is in Europe for the Copenhagen climate conference and to collect his Nobel Peace Prize in Oslo.
A spokesman for the U.S. mission in Geneva declined to comment on the state of the talks but said the two sides were committed to reaching agreement as soon as possible and the two presidents had spoken of doing so by the end of the year.
Officials at the Russian mission in Geneva dealing with arms control were not immediately available for comment.