US President Donald Trump and Russia President Vladimir Putin. Photograph:( AFP )
The US has tried to rope in China into the agreement as the Trump administration has demanded that Russia should stop its nuclear activities during the extension period.
Russia on Wednesday rejected calls over the START nuclear agreement after the Trump administration said it would support preserving the treaty for an unspecified period.
"We are in fact willing to extend the New START treaty for some period of time provided that they, in return, agree to a limitation -- a freeze -- on their nuclear arsenal," US negotiator Marshall Billingslea said.
However, deputy foreign minister Sergei Riabkov said that it was "an unacceptable proposition". The US has tried to rope in China into the agreement as the Trump administration has demanded that Russia should stop its nuclear activities during the extension period.
"Everything we agree with the Russians must be framed and must be formatted in a way that allows us to extend that arrangement to the Chinese when they are finally brought to the negotiating table," Billingslea said, however, China has rejected the US move to join the nuclear agreement with the Chinese disarmament envoy, Li Song declaring: "There are only two largest nuclear arsenals on earth. Not three."
While calling the US option as a "gentleman's agreement", the US government said it had taken "note of those who have chosen to remain silent".
Ryabkov told the Russian news agency that "a deal could even be reached tomorrow", but added that there were "many differences" even as the US side said that Russia would have to show "political will" in order to reach the agreement.
The treaty is due to expire early next year.