BUCHAREST, Romania (AP) — Typhoons from Britain's Royal Air Force based in Romania have been scrambled in response to a Russian warplane flying near NATO airspace over the Black Sea.

The RAF said the fighter jets went into action Thursday from an air base near the port of Constanta after a suspected Su-24 FENCER aircraft was spotted in the area.

In a statement, it quoted a a Typhoon pilot who was on duty as saying: "The Russian aircraft did not enter NATO airspace so we were ordered to patrol the skies for a short period of time as a deterrent, until finally returning," to the base.

The RAF mission in Romania is part of NATO's Assurance Measures introduced in 2014.

Romanian officials referred questions to NATO and the British government.