ELKO, Nevada — President Donald Trump says he will exit a landmark arms control agreement the United States signed with the former Soviet Union. He says Russia is violating the pact and it's preventing the U.S. from developing new weapons.

The 1987 pact, which helps protect the security of the U.S. and its allies in Europe and the Far East, prohibits the United States and Russia from possessing, producing or test-flying a ground-launched cruise missile with a range of 300 to 3,400 miles.

Trump said Saturday that "Russia has violated the agreement. They have been violating it for many years." The agreement has constrained the U.S. from developing new weapons, but Trump said America will begin developing them unless Russia and China agree not to possess or develop the weapons.

Deputy Foreign Minister Sergei Ryabkov was quoted as telling state news agency Tass on Sunday that "This would be a very dangerous step."

He says the Trump move "will cause the most serious condemnation from all members of the international community who are committed to security and stability."

Konstatin Kosachev, head of the foreign affairs committee in Russia's upper house of parliament, said on Facebook that a U.S. withdrawal from the treaty would mean "mankind is facing full chaos in the nuclear weapons sphere."

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