The risks to global security could be severe if the U.S. pulls out of the landmark Intermediate-Range Nuclear Forces Treaty with Russia, as President Donald Trump has pledged to do, the Kremlin warned on Sunday.

Sergei Ryabkov, Russia’s deputy foreign minister, said a unilateral U.S. withdrawal from the pact “would be a very dangerous step” that would “provoke serious condemnation” from the international community.

Ryabkov also accused the Trump administration of using the Cold War-era treaty to “blackmail” Russia.

“We see an attempt to, effectively, present Russian with an ultimatum,” he said, according to Reuters, which cited Russian media. “We will, of course, accept no ultimatums or blackmail methods.”

The INF treaty was signed in 1987 by U.S. President Ronald Reagan and Soviet leader Mikhail Gorbachev. The agreement required both nations to eliminate land-based short-range and intermediate-range nuclear and conventional missiles.

The treaty “wasn’t designed to solve all of our problems with the Soviet Union,” but “to provide a measure of some strategic stability on the continent of Europe,” former State Department spokesman Rear Adm. John Kirby told CNN.

“I suspect our European allies right now are none too happy about hearing that President Trump intends to pull out of it,” Kirby said.

President Trump: "Russia has violated the agreement. They've been violating it for many years and I don't know why President Obama didn't negotiate or pull out." https://t.co/SZxlwMe8Kj pic.twitter.com/tpbR734Yw0 — The Hill (@thehill) October 21, 2018

Trump claimed on Saturday that Russia has breached the treaty and “so we’re going to terminate the agreement.”

“We’re gonna pull out,” the president told reporters following a Nevada campaign stop.

According to Reuters, Washington believes Moscow has developed a ground-launched system that violates the treaty.

Russia, however, has denied any such violation ― and on Sunday, Ryabkov suggested it was the U.S. that had failed to comply with the pact.

The two countries have repeatedly accused each other of violating the treaty. Last year, Russia said the U.S. had run afoul of the deal in its sale of two missile defense systems to Japan.

U.S. National Security Adviser John Bolton is scheduled to arrive in Moscow on Sunday.

Ryabkov said he hopes Bolton will explain “more substantively and clearly what the American side intends to undertake.”

A split quickly emerged among Republican lawmakers in reacting to Trump’s decision to withdraw from the treaty.

Sen. Tom Cotton (R-Ark.), who has long called for U.S. withdrawal from the agreement, cheered the announcement.

Sen. Rand Paul (R-Ky.) called the move a “big, big mistake.”

This is why John Bolton shouldn’t be allowed anywhere near US foreign policy. This would undo decades of bipartisan arms control dating from Reagan. We shouldn’t do it. We should seek to fix any problems with this treaty and move forward. https://t.co/xj5FqyCyS6 #FoxNews — Senator Rand Paul (@RandPaul) October 20, 2018