In comments Saturday, President Trump announced that he has decided to withdraw the US from the Intermediate Nuclear Forces (INF) Treaty of 1987. The treaty limited both the US and Russia from having certain types of nuclear weapons.

US officials have been accusing Russia of violating the INF for years, though they have never proven it, and Russia has insisted the missiles in question were not strictly included by the ban. John Bolton has been pushing Trump on a withdrawal, while the State Department and Pentagon both opposed such a move.

Trump reiterated claims of Russian violations and also attacked President Obama for not doing something about it. Trump demanded that, now that the US has withdrawn from the treaty, Russia immediately vow unilateral compliance. He also demanded similar compliance out of China, who was never a party to INF in the first place.

The pullout was met by immediate criticism, with Mikhail Gorbachev, one of the original signatories, warning it is a reversal of decades of nuclear disarmament efforts. German Foreign Minister Heiko Maas was the first NATO official to criticize the move, saying the US should consider the consequences of the pullout for both Europe and for disarmament in general before acting unilaterally.

Russian officials faulted the US decision, saying Trump continues to “behave clumsily and crudely” around international agreements, and that the pullout is a “very dangerous step” toward an arms race.