UNITED NATIONS - The UN Security Council on Tuesday strongly condemned the third underground nuclear test conducted by the Democratic People's Republic of Korea (DPRK), saying the latest move by Pyongyang "is a grave violation" of relevant resolutions of the UN Security Council. ? ?

"The members of the Security Council strongly condemned this test, which is a grave violation of Security Council resolution 1718(2006), 1874(2009) and 2087(2013), and therefore there continues to exist a clear threat to international peace and security," said a statement read to the press by South Korean Foreign Minister Kim Sung-Hwan.

South Korea, one of the 10 non-permanent members of the 15- nation Security Council, holds the rotating council presidency for February. Kim is at the UN Headquarters in New York to chair an open debate of the Security Council on the protection of civilians in armed conflict.

DPRK said on Tuesday it has successfully conducted the third underground nuclear test, according to the official KCNA news agency.

The test was part of the country's "practical measures of counteraction" to defend its security and sovereignty against hostile U.S. policies that have violated DPRK's "rights to launch satellite for peaceful purposes," the KCNA said in a statement. ?

"The members of the Security Council recalled that in January they unanimously adopted resolution 2087, which expressed the Council's determination to take 'significant action' in the event of a further DPRK nuclear test," the statement said.

"In line with this commitment and the gravity of this violation, the members of the Security Council will begin work immediately on appropriate measures in a Security Council resolution," the statement said.

Earlier, the DPRK vowed to proceed with missile and nuclear tests targeting the United States, its "sworn enemy," after the Security Council adopted the resolution 2087 to condemn its December 12 rocket launch.

The unanimously adopted resolution 2087 says that the Security Council "condemns the DPRK's launch of 12 December 2012, which used ballistic missile technology and was in violation of resolutions 1718 (2006) and 1874 (2009)."

The Security Council "demands that the DPRK not proceed with any further launches using ballistic missile technology, and comply with resolutions 1718 (2006) and 1874 (2009) by suspending all activities related to its ballistic missiles program and in this context re-establishing its pre-existing commitments to a moratorium on missile launches," says the resolution.

Pyongyang conducted similar nuclear tests in 2006 and 2009.

Earlier on Tuesday, UN Secretary-General Ban Ki-moon condemned the test, saying it is "a clear and grave violation" of the relevant Security Council resolutions.

Ban, in a statement issued here by his spokesman, said "it is deplorable that Pyongyang defied the strong and unequivocal call from the international community to refrain from any further provocative measures."

"The secretary-general is gravely concerned about the negative impact of this deeply destabilizing act on regional stability as well as the global efforts for nuclear nonproliferation," said the statement.

Meanwhile, Ban once again urged the DPRK to reverse course and work toward denuclearization of the Korean peninsula, the statement said.