President Donald Trump's nominee for ambassador to China promised on Tuesday to take a firm line with Beijing on issues from North Korea to trade disputes and human rights, and seemed poised for an easy confirmation by the U.S. Senate.

Iowa Gov. Terry Branstad said he would use his decades of experience with China to press Beijing to do more to encourage North Korea to curb its nuclear ambitions.

"There's other things they can do diplomatically and economically to send a clear signal that they, as well as the United States and other countries in the world, do not tolerate this expansion of nuclear technology and missiles," Branstad said at his confirmation hearing.