The Russian jet breached South Korean airspace twice prompting the Air Force to scramble fighter jets and fire warning shots, an official at the Joint Chiefs of Staff told AFP.

The first violation occurred just after 9:00 am (midnight GMT Monday) and lasted three minutes.

The plane returned half an hour later, breaching the airspace for four minutes this time, the South's military said.

In response, the Air Force deployed multiple F-15k and F-16k jets to intercept the plane and fired flares after sending a message to the aircraft.

The official said it was the first time a Russian plane has violated South Korean airspace, adding that the military was investigating the matter.

The encounter occurred near the easternmost islets of Dokdo, disputed islands controlled by the South but claimed by Japan, the military said.

Seoul's defence ministry plans to lodge a protest to Russian officials later in the day.

There was no immediate comment from Moscow on the incident.