He has landed in Beijing where Chinese counterpart Xi Jinping has a lavish reception planned for him.
His arrival came just hours after his speech in the South Korean capital Seoul, in which he described North Korea as “a hell that no person deserves”.
North Korea’s nuclear weapons programme has sparked international alarm, with Pyongyang carrying out its biggest nuclear test yet in September. In typically stark language, Mr Trump warned the North: “Do not underestimate us. Do not try us.”
But there were hints though he might be open to a deal, telling the North “we will offer you a path for a better future”.
Singling out Russia and China, he urged “all responsible nations” to isolate the North, and fully implement UN sanctions, downgrade diplomatic ties and sever trade and technology ties.
“You cannot support, you cannot supply, you cannot accept,” he said.
China is North Korea’s only major ally, but says it is committed to the UN sanctions and argues its leverage is overestimated.