US president Donald Trump says his country and its allies are prepared to use military action against North Korea. But says he is open to negotiations to end Pyongyang's nuclear weapons programme.
Trump has been discussing the issue with South Korean President Moon Jae-in in Seoul.
At a joint news conference, Trump announced that South Korea will buy billions of dollars’ worth of military equipment from the US.
Al Jazeera's Tony Birtley reports from Seoul.