The European Union on Tuesday condemned North Korea's nuclear test "in the strongest possible terms", saying it was "a further blatant challenge" to the world's non-proliferation regime.
A statement from EU foreign policy chief Catherine Ashton warned that the EU "remains seized of the matter" and would work with its partners to show "the DPRK (North Korea) that there are consequences."
The latest test "is a further blatant challenge to the global non-proliferation regime and an outright violation of the DPRK's international obligations not to produce or test nuclear weapons", under UN Security Council resolutions, the statement said.
"As such, it constitutes a serious threat to a lasting peace in the Korean Peninsula and to both regional and international security and stability in North-East Asia," Ashton added.
"The EU remains seized of the matter and will work with key partners and the wider international community to build a firm and unified response aiming at demonstrating to the DPRK that there are consequences for its continued violations of UNSC resolutions," the statement warned.