South Korea's referral of the Cheonan case to the UN Security Council constitutes an "unbearably provocative" act toward the Democratic People's Republic of Korea (DPRK), said the country's reunification body on Sunday.

South Korean naval ship, the Cheonan, sinks near South Korea's Baeknyeong Island, close to DPRK, in the western waters on Saturday, March 27, 2010. [Xinhua/Reuters File Photo]

The South Korean move is a "very dangerous" one as it will heighten the tense situation on the Korean Peninsula and create the dangers of war, the Secretariat of the Committee for the Peaceful Reunification of Korea warned in an information bulletin, according to the official KCNA news agency.

DPRK will not tolerate this kind of "provocative act" by South Korea, said the bulletin, adding if South Korea continues this "smear campaign" to escalate confrontation with the DPRK, "it will not be able to escape stern punishment by the army and people of the DPRK."

The South Korean "Cheonan" warship sank on March 26 near the maritime border with the DPRK after an explosion, killing 46 sailors. According to investigation results released by South Korea, the 1,200-ton ship was torpedoed by a DPRK submarine.

The DPRK has denied any involvement in the sinking, saying the incident was just a farce orchestrated by South Korea.

South Korea officially referred the case to the UN Security Council on Saturday.