UNITED NATIONS: The UN Security Council “strongly condemned” on Tuesday North Korea’s third nuclear test and vowed to take action against the country, the president of the Security Council said.

“The members of the Security Council strongly condemned this test, which is a grave violation of Security Council resolutions,” South Korean Foreign Minister Kim Sung-hwan, whose country is president of the council this month, told reporters. He said the council would now consider “appropriate measures”.

A press statement approved by all 15 members of the council at an emergency meeting hours after the latest underground test called the blast a “grave violation” of three UN resolutions banning the North from conducting nuclear or missile tests.

North Korea said in a statement the test was an act of self-defence against “US hostility” and threatened further, stronger steps if necessary.

Monitoring stations in South Korea detected an earthquake in the North with a magnitude of 4.9 and the South’s Defence Ministry said that corresponded to an estimated explosive yield of 6-7 kilotons.

The United States Geological Survey said earlier that it had detected a magnitude-4.9 earthquake.