Russia said Wednesday that it will continue following the nuclear arms limits of the expired New START treaty if the U.S. does.

The treaty expired Thursday, leaving no restrictions on the two largest atomic arsenals for the first time in more than 50 years, The Associated Press reported.

Last year, Russian President Vladimir Putin said he was ready to follow the treaty’s limits for another year if the U.S. did so. But President Trump has argued that he wants China to be a part of a new pact. However, China has rejected joining a nuclear arms treaty.

Russian Foreign Minister Sergey Lavrov told the Russian Parliament’s lower house Wednesday that even though the U.S. hasn’t responded to Putin’s offer, Russia will respect New START’s limits for as long as the U.S. observes them.

“The moratorium declared by the president will remain as long as the U.S. doesn’t exceed these limits,” he said. “We will act in a responsible and balanced way on the basis of analysis of the U.S. military policies.”

Lavrov also said: “We have reason to believe that the United States is in no hurry to abandon these limits and that they will be observed for the foreseeable future.

“We will closely monitor how things are actually unfolding. If our American colleagues’ intention to maintain some kind of cooperation on this is confirmed, we will work actively on a new agreement and consider the issues that have remained outside strategic stability agreements.”