Defying the UN Security Council's statement on Oct. 6, 2006 and the calls of the international community, DPRK's test jeopardizes profoundly regional stability and represents a severe threat to international peace and security, the Finnish Presidency of the 25-nation bloc said in a statement.

It is a flagrant breach of the December 1991 North-South Denuclearization Declaration. Furthermore, it conflicts completely with the Security Council Resolution 1695 unanimously adopted after DPRK test-fired ballistic missiles in early July, the statement said.

The EU strongly urged DPRK to announce immediately that it would refrain from any further tests of nuclear devices, publicly renounce nuclear weapons, return to the six-party talks immediately without preconditions, work towards implementation of the Joint Statement of September 2005, and, in particular, abandonall nuclear weapons and existing nuclear programs.

The EU also urged DPRK to return to full compliance with the Non-Proliferation Treaty, and to sign and ratify the Comprehensive Nuclear-Test-Ban Treaty.

DPRK's official Korean Central News Agency announced on Monday that the country had conducted a successful underground nuclear test.

The nuclear test, the first of such performed by DPRK, came about a week after the country announced it would carry out an unprecedented atomic test under the condition where safety was firmly guaranteed.