President Donald Trump announced Wednesday that he has ordered the Defense Department to begin nuclear weapons testing to match China and Russia.

He said the U.S. already holds the world’s largest and most advanced nuclear arsenal, rebuilt during his first term.

The move comes ahead of his meeting with Chinese President Xi Jinping in South Korea and marks the first potential return to explosive testing since 1992, The Hill has reported.

Trump’s decision follows recent Russian nuclear tests and echoes calls from former adviser Robert O’Brien for renewed U.S. testing amid stalled arms control talks.