President Trump has announced plans to pull the United States out of a landmark nuclear arms pact with Russia, in a move that could spark a new arms race. President Ronald Reagan and former Soviet leader Mikhail Gorbachev signed the Intermediate-Range Nuclear Forces—or INF—Treaty in 1987. The INF banned all nuclear and non-nuclear missiles with short and medium ranges. The treaty helped to eliminate thousands of land-based missiles. Trump spoke about his decision on Saturday.

President Donald Trump: “Russia has violated the agreement. They’ve been violating for many years, and I don’t know why President Obama didn’t negotiate or pull out. And we’re not going to let them violate a nuclear agreement and go out and do weapons, and we’re not allowed to. We’re the ones that have stayed in the agreement, and we’ve honored the agreement. But Russia has not, unfortunately, honored the agreement. So we’re going to terminate the agreement. We’re going to pull out.”

President Trump did not offer details on how Russia was violating the deal. Over the years, Russia has also accused the United States of violating the agreement by deploying missiles in Romania. National Security Adviser John Bolton, who has advocated against the treaty, is now in Moscow for talks with Russian Foreign Minister Sergey Lavrov and President Vladimir Putin. China and France spoke out against the move, with the Chinese Foreign Ministry saying, “The document has an important role in developing international relations, in nuclear disarmament, and in maintaining global strategic balance and stability.” We’ll have more on the U.S.-Russia treaty after headlines with the director of the Arms Control Association, Daryl G. Kimball.