U.S. President Barack Obama accused Russian President Vladimir Putin of slowing progress on nuclear arms reduction by focusing instead on building up Moscow's military might.
"My preference would be to bring down further our nuclear arsenal," Obama said at a press conference on April 1 after his two-day Nuclear Security Summit in Washington.
The Obama administration approached Russia about a possible new phase in arms reduction talks in 2010 after Russia and the United States signed the Strategic Arms Reduction Treaty II.
But no further negotiations ensued, and Obama said that was "because of the vision that [Putin has] been pursuing of emphasizing military might over development."
Putin, who boycotted the summit attended by dozens of other world leaders, said in June that Russia would add more than 40 intercontinental ballistic missiles to its nuclear arsenal to modernize its program and overcome NATO anti-missile defense systems near its border.
Obama said the possibility of progress in future years on arms reductions with Russia remains as both countries continue to abide by the START agreement. But he said reductions during his remaining 10 months in office are unlikely.