MOSCOW—Russian President Vladimir Putin raised the prospect of an arms race with the U.S. on Wednesday in response to Washington’s warning it could suspend a Cold War-era treaty that prohibits intermediate and shorter-range nuclear missiles.
The end of the pact would be the latest dent to U.S.-Russia relations and severely undermine the decades-old nuclear-arms control architecture built up during the Cold War.
It could also accelerate the Pentagon’s initial research into the development of missiles banned by the agreement.
The head of the Russian armed forces warned that if the deal collapses, the targets of subsequent military exchanges would be U.S. missile sites hosted by allies within striking distance of Russia rather than American soil.
The U.S. has accused Russia of violating the Treaty on Intermediate-range Nuclear Force, and Secretary of State Mike Pompeo said on Tuesday that Washington would freeze its commitments under the treaty in 60 days if Russia didn’t comply with the pact. Russia denies violating the treaty and accuses the U.S. of having done so.
Mr. Putin said Russia would “respond appropriately” if the U.S. withdrew from the agreement, and indicated that Moscow would develop and construct shorter and intermediate-range weapons if the U.S. did so.
“Our American partners apparently believe that the situation has changed to such an extent that the U.S. should have such weapons,” said Mr. Putin, speaking on state TV.
“What answer will they have from our side? It’s simple: we’ll do it too.”
U.S. withdrawal from the pact could spur on the Pentagon’s preliminary research and development into reviving an arsenal of the type prohibited under the treaty, according to U.S. officials. Washington has informed Moscow of its research efforts in that direction in an attempt to gain Russian compliance with the treaty.
Any such Pentagon program risks an arms race with Russia or even China, since Beijing isn’t party to the treaty and has deployed short and intermediate -range missiles in significant numbers. President Trump has said the INF treaty puts the U.S. at a disadvantage against rival China.
Washington points to Moscow’s 9M729 cruise missile project, which has been in progress for years, as evidence Russia has violated the treaty, accusing Moscow of testing a missile within the range barred in the agreement. Missiles that can strike at a distance of between 300 and 3,400 miles contravene treaty limits.
Russian Deputy Foreign Minister Sergei Ryabkov said last month that a missile flew its maximum distance—within the boundaries of the treaty—in a test during military exercises with North Atlantic Treaty Organization members in Sept. 2017.
Hard facts about Russia’s development and use of banned missiles are difficult to pin down, said Pavel Podvig, a senior research fellow at the U.N. Institute for Disarmament Research.
But Moscow has long seen the 1987 deal as preferential to the U.S., which wouldn’t be within striking distance of Russian intermediate-range missiles.
Russia says that the U.S. has broken the INF agreement by basing missile-defense systems in Europe that Moscow argues can be used to launch strikes on Russia.
In an apparent attempt to pressure the U.S.’s Western allies Wednesday, the head of Russia’s armed forces Valery Gerasimov warned foreign military attachés that the U.S. wouldn’t likely be affected by the fallout from the end of the nuclear agreement.
“But rather the countries that have based American systems on their territory,” he said.
Russia, which has a military budget less than a 10th the size of that of the U.S., wouldn’t want to devote massive resources to a new arms race. But Mr. Putin, who has personally backed a multibillion-dollar military modernization, has staked his popularity on revamping the country’s armed forces and advancing Russia’s interests against the West.
The treaty at the heart of the debate was signed by President Ronald Reagan and Mikhail Gorbachev, the Soviet leader, and is widely seen as one of the landmark agreements that sealed the end of the Cold War. Nearly 2,700 American and Russian missiles were destroyed under the accord, which applies to missiles based on land and not to those fired by aircraft or based at sea.
The U.S. allegation that Russia had violated the agreement was first made public by the Obama administration in 2014. At that point, the Russian missile was in the testing phase, and Mr. Obama sent a letter to Mr. Putin that year urging a high-level dialogue with the aim of preserving the agreement.
At first, Obama administration officials said, the Russians did not acknowledge developing the missile and talks to resolve the dispute went nowhere. In 2017, U.S. concerns about the program deepened when Air Force Gen. Paul Selva, the vice chairman of the Joint Chiefs, told Congress that the weapons had moved beyond the test phase and had been deployed.
While Mr. Putin has insisted that Russia has upheld the accord, he told Russian defense industry officials in June 2013 that Mr. Gorbachev’s decision to conclude the treaty was “debatable to say the least.” Some Russian officials have long argued that the accord affected Russia more than the U.S as it precluded Moscow from fielding new weapons to deal with threats on its periphery, such as China and Pakistan.
While it is very unlikely that NATO nations would welcome the deployment of new U.S. intermediate-range missiles based on land, some U.S. military officials have suggested that such weapons might be a useful counter to China, which is not a party to the 1987 agreement.
—Michael R. Gordon in Washington contributed to this article.
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