Russian President Vladimir Putin upped the ante Wednesday by saying he is prepared to develop nuclear-tipped missiles if the U.S. withdraws from a Cold War-era arms agreement.
Putin, in televised comments, said Moscow would develop midrange nuclear missiles, a weapon that is currently banned from U.S. and Russian arsenals under the Intermediate-Range Nuclear Forces, or INF, treaty.
The INF treaty, signed in 1987 between President Ronald Reagan and Soviet leader Mikhail Gorbachev, prohibited the development and deployment of ground-launched nuclear missiles with ranges of 310 miles to 3,420 miles.
President Donald Trump has promised to withdraw from that treaty, claiming Russia has been cheating. Secretary of State Mike Pompeo offered an ultimatum to Russia on Tuesday. The Russian leader suggested the U.S. was the one itching to escalate the arms race.
"Now it seems our American partners believe that the situation has changed so much that the United States must also have such a weapon. What's our response? It's simple: in that case we will also do this," Putin said.
U.S. arms experts said the Kremlin needs to take responsibility.
"Russia's violation is unacceptable and requires a firm U.S. and NATO diplomatic, economic and treaty-compliant military response strategy," Kingston Reif, director of disarmament research at the Arms Control Association, told CNBC following Putin's remarks.
"Russia's had treaty-violating missiles for years, so they're not fooling anybody by alleging that they'd have to start building treaty-violating missiles. It's a transparent ploy to put the onus back on the U.S., but it won't work," said Thomas Karako, director of the Missile Defense Project at the Center for Strategic and International Studies.
Putin's response came a day after Secretary of State Mike Pompeo cited material evidence that Russia has quietly added nuclear-tipped missiles that are currently banned by the INF treaty to its colossal arsenal.
Russia, Pompeo said, has developed "multiple battalions of the SSC-8 missiles," a move that falls outside of the Cold War-era arms agreement.