Putin says Russia will begin to work on intermediate-range weapons | Ozan Kose/AFP via Getty Images Putin quits missile treaty with US in ‘quid pro quo’ with Trump Russian leader pledges not to station new weapons in Europe ‘until similar US weapons appear.’

Russia is abandoning a key missile treaty the day after the United States said it is suspending participation, renewing concerns about a nuclear arms race between the two countries.

“We will respond quid pro quo,” President Vladimir Putin said Saturday, according to the Associated Press. “Our American partners have announced they were suspending their participation in the treaty and [we] will do the same."

“They have announced they will conduct research and development, and we will act accordingly,” he continued.

Putin said Russia would begin to work on intermediate-range weapons. He pledged Russia would “not station” any of these weapons “in Europe or other regions until similar U.S. weapons appear in those regions,” AP reported.

U.S. officials have indicated they will move ahead with "fielding systems that will continue to protect Americans abroad and Americans at home."

The Trump administration said Friday it would withdraw from the 1987 Intermediate-Range Nuclear Forces Treaty, alleging Russia has been violating its treaty obligations for years. The treaty bans “nuclear and conventional ground-launched ballistic and cruise missiles with ranges of 500 to 5,500 kilometers,” according to the Arms Control Association.

The U.S. said it would reconsider its participation if Russia eliminates its new 9M729 cruise missile system. The EU countries and other allies that make up the North Atlantic Treaty Organization backed the U.S. in a statement released Friday, saying Russia “will bear sole responsibility for the end of the Treaty” if it does not destroy the new system.

China’s Ministry of Foreign Affairs opposed the U.S. withdrawal action in a statement Saturday, urging the two countries to “handle their differences properly through constructive dialogue,” Reuters reported.