Washington has again called on Moscow to take "demonstrable steps" to save a key Cold War arms-control treaty, and reiterated claims that Russia's behavior is not that of a "responsible state actor."

The United States "increasingly finds that Russia cannot be trusted to comply with its arms-control obligations, and that its coercive and malign actions around the globe have increased tensions," Robert Wood, the U.S. ambassador to the UN-sponsored Conference on Disarmament, said on January 21, amid severely strained relations between Moscow and Washington.

The United States said it will exit the 1987 Intermediate-Range Nuclear Forces (INF) Treaty in early February if Russia does not dismantle the weapon that Washington says violates it.

Russia denies the missile in question -- referred to as the SSC-8 or 9M729 -- violates the bilateral treaty limiting medium-range missiles.

Russia's "actions, policies, and behavior are not those of a responsible state actor," Wood told a meeting of the Conference on Disarmament in Geneva.

He said there was "only one path forward" for Moscow to return to compliance with the INF Treaty: to "verifiably destroy all SSC-8 missiles, launchers, and associated equipment."

"Inertia will not drive policy in the Trump administration and the United States will not stand idly by when others cheat on international agreements," the U.S. envoy warned.

Following Wood's comments, Russia's deputy disarmament ambassador, Aleksandr Deineko, said that "making one-sided allegations is not a constructive way forward."

"We shall not yield to any ultimatums, like to liquidate or to eliminate a missile that does not fall within the range of a treaty's prohibitions," Deineko told Reuters in Geneva.

Speaking last week following talks in the Swiss city on the INF Treaty, a senior U.S. official said Moscow was refusing to allow proper inspection of the missile system that Washington says violates the accord.