Russia has expressed deep regret after a Russian aircraft violated South Korean airspace on Tuesday.

Presidential Secretary for Public Relations Yoon Do-han said in a news briefing on Wednesday that Moscow has informed Seoul that it will immediately launch an investigation and take all necessary measures related to the incident.

Yoon said that the Russian deputy military attache told the South Korean Defense Ministry's director general for policy planning on Tuesday that a Russian aircraft appears to have entered an unplanned area due to an equipment malfunction.

The Russian official said that it will help shed light on the incident if South Korea hands over information on the time of the trespass, the location coordinates and pictures. 

The official added that Tuesday's flight was a pre-planned joint exercise with China and that if its aircraft had followed the planned route, it wouldn't have violated Korean airspace. 

The official said that Russia respects international as well as Korean domestic laws and that the intrusion wasn't intentional, adding that Russia hopes to advance its relations with South Korea regardless of the latest incident.