At least ten U.S. Air Force refuelling tankers left RAF Mildenhall on Monday and reached other American bases in Europe plus Prestwick Airport in Ayrshire, according to flight tracking reported by BBC Verify. The Wall Street Journal linked the flights to an Iranian threat whose timing was unspecified, coming weeks after bombers were pulled from RAF Fairford following a suspected Iran-linked security incident.

Two of the tankers first flew toward Germany and Italy; one KC-135 later arrived at Spangdahlem after a brief return, and the second reached the same German base after flying near Aviano, while three Osprey tiltrotors arrived at RAF Lakenheath on Tuesday, CBS News reported. A Ministry of Defence spokesperson said the department does not as a rule discuss other countries operations and that aircraft relocate as operational needs require. Lord Ricketts said sizable tankers at a base with an extensive boundary are exposed and that unknown information likely led to extra caution.