Russian President Dmitry Medvedev on Saturday said the replacement for the START nuclear arms reduction treaty, currently in the final stages of negotiation, would need to be simultaneously ratified in the US, Ria Novosti reported.
"I think our American partners must know this," Medvedev said, dpa reported.
It could not happen that Moscow would ratify the treaty and Washington not, as happened in Soviet times, the report quoted Medvedev as saying.
The new treaty would have to be ratified by the US Senate and Russian Duma.
In late December, US President Barack Obama met with Medvedev on the sidelines of the Copenhagen climate conference to discuss the state of the negotiations for the replacement to START, which expired December 5.
"We've been making excellent progress. We are quite close to an agreement, and I'm confident it will be completed in a timely fashion," Obama then said.
Medvedev on Saturday said that the negotiations were "not easy, but basically positive."
"We agree with the Americans on many points," he said.
The goal of the new accord is reportedly to cut the number of nuclear warheads to a maximum of 1,675 per country, while limiting delivery systems to 1,100 each.
Russian Prime Minister Vladimir Putin recently said Russia would continue to develop offensive missiles even given a new nuclear arms reductions treaty.
Speaking in Vladivostok, Putin said this would help Russia "to maintain the balance of power."