Lieutenant General H.R. McMaster will resign as Trump’s national security adviser and be replaced by John Bolton, former U.N. ambassador under President George W. Bush, the White House has announced. Bolton is a foreign policy hawk who has suggested the U.S. military should directly engage Iran and North Korea.

The White House previously denied media reports that President Trump was poised to fire McMaster ahead of a planned U.S.-North Korea summit in May.

John Bolton was named by President George W. Bush in 2005 to be the U.S. ambassador to the United Nations in a recess appointment, after Bush feared he would not be confirmed by the Senate. Bolton is a foreign policy hawk who has suggested the U.S. military should directly engage Iran and North Korea. He once said if the U.N. headquarters in New York lost 10 stories, “it wouldn’t make a bit of difference.” The position of national security adviser does not require Senate confirmation.