South Korea said its F-15K and F-16K jets scrambled to intercept the Russian plane (File)

South Korean warplanes fired hundreds of warning shots at a Russian military aircraft that entered South Korean airspace on Tuesday, defence officials in Seoul said, with Chinese bombers also entering South Korea's air defence identification zone.

It was the first time a Russian military aircraft had violated South Korean airspace, an official at the Ministry of National Defence in Seoul said.

Two Russian bombers and two Chinese bombers entered the Korea Air Defence Identification Zone (KADIZ) together early on Tuesday, the defence ministry said.

A separate Russian early warning and control aircraft later twice violated South Korean airspace over Dokdo - an island that is occupied by South Korea and also claimed by Japan, which calls it Takeshima - just after 9 a.m. (midnight GMT Monday), according to the South Korean military.

There was no immediate public comment from Russia. China's foreign ministry did not respond immediately to a Reuters request for comment.

South Korea's top security adviser Chung Eui-yong lodged a strong objection with Nikolai Patrushev, secretary of the Security Council of Russia on Tuesday, asking the council to assess the incident and take appropriate action, South Korea's presidential office said.

"We take a very grave view of this situation and, if it is repeated, we will take even stronger action," Chung said, according to South Korea's presidential office.

South Korea's Foreign Ministry plans to summon acting Russian Deputy Chief of Mission Maxim Volkov and Chinese Ambassador Qiu Guohong on Tuesday to lodge a stern protest and strongly urge them to prevent a recurrence, ministry spokesman Kim In-chul said.

The Russian aircraft was an A-50 airborne early warning and control aircraft, an official at South Korea's Joint Chiefs of Staff (JCS) said, and South Korea scrambled F-15 and F-16 fighter jets in response to the intrusions.

The South Korean jets fired around 360 rounds of ammunition during the incident, the JCS official said.

"The South Korean military took tactical action including dropping flares and firing warning shots," the defence ministry said.

A South Korean defence official told Reuters that the Russian aircraft did not respond in any threatening way.

The Russian aircraft left South Korean airspace but then entered it again about 20 minutes later, prompting the South Koreans to fire more warning shots.

The ministry said South Korean warplanes "conducted a normal response" to the incursion, without giving further details.