Russia has formally proposed to the United States that the two nuclear superpowers extend their New START arms control treaty by five years, though Moscow would also settle for a shorter extension, a senior Russian official said on Wednesday.The New START accord, which is due to expire in February 2021, is the last major nuclear arms control treaty between Moscow and Washington. It limits the number of strategic nuclear warheads they can deploy to 1,550 each.Russia warned earlier this month there was already not enough time left for Moscow and Washington to negotiate a full-fledged replacement to the treaty and that time was running out to agree on an extension."We proposed to the United States extending the treaty by five years as stipulated in it, or, if for some reason that is uncomfortable for the U.S. side, then for a shorter period of time...," Deputy Foreign Minister Sergei Ryabkov said on Wednesday, RIA news agency reported.Ryabkov, who made the comments after meeting his Chinese counterpart in China, said a shorter extension would not be the best outcome, but that it would be "at least better than nothing."U.S. President Donald Trump told Russia's President Vladimir Putin in 2017 he thought the New START accord was a bad deal for the United States. U.S. officials say he will only decide next year whether or not to extend the treaty.It was signed by Trump's predecessor, Barack Obama, in 2010.