Britain’s Royal Air Force and the French Air and Space Force held the first joint nuclear exercise between the two countries involving France’s airborne nuclear deterrent, France’s armed forces ministry said in a statement on Friday.

British Typhoon jets joined in a nuclear exercise alongside French Rafale warplanes on Tuesday evening, French armed forces minister Catherine Vautrin said, reported the Independent, which called it a “warning shot to Putin.”

“Having independent nuclear forces does not preclude coordination,” Vautrin said, adding: “Our nuclear cooperation with the United Kingdom continues to deepen.” She said the exercise showed the “coordination and commitment” of the two European nuclear powers “in support of Europe’s security and credible deterrence.”