North Korea claimed on Monday that it has performed its first-ever nuclear weapons test.

The test was performed and there has been no radioactive leakage from the site, the country's official Korean Central News Agency said.

"The nuclear test is a historic event that brought happiness to the our military and people. It will contribute to maintaining peace and stability in the Korean peninsula and surrounding region," KCNA said.

Intelligence about the test has been exchanged between many countries.

South Korean President Roh Moo-hyun has convened a meeting of security advisers over the issue, South Korea's Yonhap news agency reported.

Yonhap reported that North Korea's nuclear test was conducted at 0706 IST in Hwaderi near Kilju city, citing defence officials.

North Korea had said last week it would conduct a test. The country has long claimed to have nuclear weapons, but had never before performed a known test.

Meanwhile, South Korea's intelligence agency has detected a 3.58-magnitude seismic tremor, a foreign ministry spokesman said on Monday, following North Korea's announcement of a nuclear test.

However, US intelligence has said that they cannot confirm whether N Korea has conducted a nuclear test.