Mikhail Gorbachev, the former president of the Soviet Union, criticized President Donald Trump's threat to withdraw from an international nuclear disarmament treaty, saying the move "is not the work of a great mind."

Trump announced at a rally Saturday that he will pull the U.S. from the "Intermediate-Range Nuclear Forces Treaty," (INF) citing Russian violations of the deal, although he did not give further details.

The 1987 treaty prohibits Russia and the U.S. from possessing, producing or test-flying a ground-launched cruise missile having a range of 500 to 5,500 kilometers or "to possess or produce launchers of such missiles."

Gorbachev, who led the Soviet Union from 1985 until its dissolution in 1991, had signed the treaty with then-U.S. President Ronald Reagan.

Now 87, Gorbachev said Trump's decision was "very strange" and a mistake.

"Do they really not understand in Washington what this can lead to?" Gorbachev told Russian news agency Interfax on Sunday, adding that the decision "will undermine all the efforts that were made by the leaders of the USSR and the United States themselves to achieve nuclear disarmament."

Gorbachev said that "Washington's aspiration to turn politics back cannot be supported, this must be declared not only by Russia, but by all who cherish the world, especially the world without nuclear weapons."

The treaty marked a historic shift in U.S.-Russian relations and came at a time of Gorbachev-led reforms in Russia — most notably, his policies of "perestroika" and "glasnost" — essentially, a series of political and economic reforms and "openness."

Gorbachev said Sunday that "all agreements aimed at nuclear disarmament and the limitation of nuclear weapons must be preserved for the sake of life on Earth."