Russia accused the U.S. of stalling progress on nuclear disarmament Tuesday after the Obama administration revealed that the Kremlin has continued to increase its arsenal of strategic warheads.

“Relations between our countries suffered a sharp worsening due to deliberate destructive actions by the United States, taken on the excuse of a Russian aggression. All this is accompanied by growing anti-Russian rhetoric,” said Foreign Ministry spokeswoman Maria Zakharova, Russian news agency TASS reported. “We remain prepared for conducting a specific discussion with the United States on strategic affairs, although the climate for such a dialogue is not the most favorable of all through its fault.”

Zakharova went on to blame the U.S. for being “very selective” in approaching arms control issues. Russia President Vladimir Putin was noticeably absent from last week’s nuclear summit in Washington, D.C.

The U.S. State Department revealed Friday that Russia has continued increasing its arsenal despite having agreed to a reduction with the U.S. that comes into effect in 2018 under the new START treaty. The treaty requires strategic warheads be reduced to 1,550 by February 2018. While the U.S. stockpile is currently at 1,481 warheads, Russia’s count is at 1,735 with an increase of 153 warheads added in the last year, the Moscow Times reported.

“My personal view is that Russia no longer sees value in that [security] architecture put in place at the end of the Cold War,” said Frank Rose, U.S. assistant secretary for arms control, the Financial Times reported. “They are slowly but surely taking out the key building blocks of the Euro-Atlantic architecture put in place in the late '80s and '90s.”

In his concluding remarks at the summit, President Barack Obama said work remained to be done between the U.S. and Russia to reduce nuclear stockpiles, but with Putin emphasizing “military might” this would remain unlikely. Russia and the U.S. hold the largest nuclear stockpiles in the world. Zakharova argued conditions for discussions were not possible without mutual respect.