The UN Security Council is holding an emergency meeting after North Korea fired what it said was a satellite into space.
Minister for Foreign Affairs Charlie Flanagan has condemned the blast off - saying it's a serious and direct threat to peace and stability in the region and beyond.
He has called on the country to refrain from further action that could increase tensions.
The incident has received global criticism and is seen as a thinly disguised missile test.
Japanese Prime Minister Shinzo Abe has said he will work with the international community to take "appropriate measures": “We will not tolerate North Korea going ahead with the launch after repeated warning to restrain themselves.
“The Missile launch following the nuclear testing is a clear violation of the UN security council resolutions.”