Western allies should not describe the acts of Russian military aggression against Ukraine that would “trigger” trans-Atlantic penalties, according to a senior British official who cautioned against focusing overmuch on Russian tanks.

“We don’t want to go into too much detailing exactly what might be the trigger,” British lawmaker James Cleverly, the United Kingdom Foreign Office’s lead minister for North America, told reporters Monday during a visit to Washington. “I think a lot of people are calibrating their thinking to something like what we see in the movies — lots of tanks, lots of troops. But we also know Russia are experts in a whole spectrum of aggressive, disruptive actions that might fall short of what would be regarded as an ‘invasion.’”