Russia said on Monday it would hold a military exercise that will include practice for the use of tactical nuclear weapons after what the defence ministry said were provocative threats from Western officials.

An American official said the United States had information undermining Russia’s claim that a device it is developing is for peaceful scientific research.

The drills come in response to “provocative statements and threats of certain Western officials regarding the Russian Federation,” the Defense Ministry said in a statement. It was the first time Russia has publicly announced drills involving tactical nuclear weapons,