The world is on alert after North Korea confirmed the successful testing a small nuclear device earlier today.

The United Nations has also confirmed that this detonation — which was first thought to be an earthquake — was larger than North Korea’s previous nuclear tests, measuring 4.9 on the Richter scale.

President Obama has called this action a highly provocative act. In a statement released earlier this morning, he said,

“These provocations do not make North Korea more secure. Far from achieving its stated goal of becoming a strong and prosperous nation, North Korea has instead increasingly isolated and impoverished its people through its ill-advised pursuit of weapons of mass destruction and their means of delivery.”

South Korea and China, too, have been critical of the nuclear measures in North Korea.

President Obama is calling upon the U.N. security council to take action in order to curb North Korea’s nuclear ambitions.