China says the United States has inflamed the conflict on the Korean Peninsula and must carry the burden of ending it in the wake of North Korea's fifth nuclear test.

North Korea is ready to conduct an additional nuclear test at any time, South Korea's Defence Ministry said on Monday, three days after the reclusive North's fifth test drew widespread condemnation.

North Korea has hit the button on its fifth and potentially most powerful nuclear test, claiming to have successfully tested a nuclear warhead.

The foreign ministers of China, Japan and South Korea put aside frictions over territorial disputes and wartime history to sharply criticize North Korea's latest submarine missile test on Wednesday in a rare display of unity.

Two major security concerns, a rising China and a nuclear North Korea, have prompted the Pentagon to endorse a plan to invest $7.5 billion to strengthen the U.S. presence in the Asia-Pacific region over the next five years. However, it remains to be seen how this fits with Trump administration’s broader policy and military posture for the Asia Pacific.