Speaking after talks Wednesday with Finnish President Sauli Niinisto, Putin argued that the quick test indicated the U.S. had begun work on the missile long before declaring its intention to withdraw from the pact.
"The Americans have tested this missile too quickly after having withdrawn from the treaty," Putin said. "That gives us strong reason to believe that they had started work to adapt the sea-launched missile long before they began looking for excuses to opt out of the treaty."
The U.S. has explained its withdrawal from the treaty by Russian violations — the claim Moscow has denied.
The Russian leader said that Russia would also work to design such weapons, but reaffirmed that it wouldn't deploy the missiles previously banned by the INF Treaty to any area before the U.S. does that first.
Putin charged that Sunday's test was performed using a launcher similar to those stationed at a U.S. missile defense site in Romania. He argued that the Romanian facility and a prospective similar site in Poland could also be used for missiles intended to hit ground targets instead of interceptors.
"Such missiles could be launched from facilities in Romania, as well as those to be deployed in Poland," he said. "It only requires software tweaks. I'm not sure that our American friends will share the information about which software they use even with their European partners."
He said that for Russia that means "the emergence of new threats, to which we will react accordingly."