US: Russia 'violated missile treaty' Russia has violated a key arms control treaty by testing a nuclear cruise missile, the US government says. Russia tested a ground-launched cruise missile, breaking the Intermediate-Range Nuclear Forces Treaty signed in 1987 during the Cold War, the US said. A senior US official did not provide further details on the alleged breach, but described it as "very serious". The bilateral agreement banned medium-range missiles with ranges between 500 and 5,500 km (300 to 3,400 miles). The US claims come at a time of heightened tensions between the two sides, with the US criticising Russia for its alleged involvement in the conflict in Ukraine. A senior US official, who was not named, said in a statement that the testing of the missile was "a very serious matter which we have attempted to address with Russia for some time now". "We encourage Russia to return to compliance with its obligations under the treaty and to eliminate any prohibited items in a verifiable matter," the official added. BBC