What Happened During an arms control forum on May 29, U.S. Defense Intelligence Agency Director Lt. Gen. Robert Ashley Jr., said that Russia was likely in violation of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). In response, Russia's ambassador to the United States stated that the allegations looked like "a well-planned and directed attack." Meanwhile, the head of the Russian State Duma Defense Committee Vladimir Shamanov has said that Washington "could not have made a more irresponsible statement," adding that "nuclear tests cannot be carried out secretly." Why It Matters This is not the first time that the United States has raised questions over both Russia and China's full adherence to the CTBT. Washington also left some space for continued negotiations by saying Moscow was "likely" — but not definitely — in breach of the treaty.