North Korea rocket
A flying object soars into the air above North Korea as seen from the Chinese border city of Dandong on 7 FebruaryKyodo/Reuters

The South Korean navy has fired warning shots at a North Korean boat after it crossed a disputed maritime border, further raising the stakes in the Korean peninsula tensions. The naval encounter comes a day after Pyongyang fired off a long-range rocket defying global warnings.

Seoul's defence ministry said the North's vessel entered the tense waters about 7am local time on Monday (8 February). The de facto maritime boundary, known as the Northern Limit Line, has experienced serious confrontation between the nations in the past as well.

The line separating the two countries was drawn up at the close of the 1950-53 Korean War but both countries have struggled with the frontiers delimitation ever since and the countries are technically still at war.

South Korean forces have been kept on high alert after the North blasted off a rocket over the weekend violating UN resolutions. Though Pyongyang labels the launch as an attempt to put a satellite in orbit, it is widely seen as a test for its ballistic missile technology.

An emergency session of the UN Security Council was also convened at the joint request of Japan, South Korea and the US. Pledging to implement a fresh spate of resolutions against the North, the council's current president and Venezuelan UN Ambassador Rafael Dario Ramirez Carreno said: "The members of the Security Council strongly condemn this launch.

"The members of the Security Council underscore this launch as well as any other DPRK launch that use ballistic missile technology even if characterised as a satellite launch or a space launch vehicle contribute to the DPRK's nuclear weapon delivery system and is a serious violation of the Security Council resolutions."

The council's president added: "In line with this commitment and the gravity of this most recent violation, the council will adopt expeditiously a new security council resolution with such measures in response to this dangerous and serious violation." The North's latest rocket launch comes weeks after it conducted a nuclear test — both acts violate UN regulations.