US President Donald Trump reaffirmed his vow to destroy the Islamic State group and "protect civilization" during a White House press conference on Wednesday.

Speaking after talks with Jordan's King Abdullah, Trump predicted that the campaign against IS in Syria and Iraq will be "a shorter fight than a lot of people are thinking about, believe me."

"We will destroy ISIS, and we will protect civilization. We have no choice," he said, using an alternate acronym for IS.