Secretary of State Mike Pompeo said Wednesday that the United States is making progress in its negotiations with Russia on arms control.

“In the last handful of months, we’ve been working diligently to get the three nations that have the largest nuclear capabilities - the United States, Russia and China - to have strategic dialogue about how we move forward together to decrease the risk to the world,” Pompeo told reporters.

“We’ve made progress with the Russians; we’ve had two good gatherings. I hope we’ll have one before too long, and we’re hopeful that the Chinese will choose to participate,” he said.

The U.S. and Russia are months away from the expiration of the last major nuclear arms reduction treaty between them: New START. The deal limits the number of deployed strategic nuclear warheads to 1,550 for each country and expires on Feb. 5, 2021.

President Trump has previously suggested that he would like to make a deal with Russia on arms control.

“If we can do something with Russia in terms of nuclear proliferation, which is a very big problem — bigger problem than global warming, a much bigger problem than global warming in terms of the real world — that would be a great thing,” Trump told Axios reporter Jonathan Swan in a recent interview.

The Trump administration has backed out of several security and nuclear agreements with Russia.

In May, the Trump administration announced its intent to withdraw from the 1992 Open Skies Treaty, which launched a program of unarmed aerial surveillance flights over the U.S., Russia and other countries. The goal of the treaty is to promote transparency of military forces and activities.

In August, the U.S. formally withdrew from the Intermediate-Range Nuclear Forces Treaty (INF), an agreement signed in 1987 by President Ronald Reagan and Soviet leader Mikhail Gorbachev. The deal bans missiles with ranges of up to 3,400 miles.

The U.S. has accused Russia of violating the INF agreement, with Moscow denying the allegations.