Trump and Secretary of Defense James Mattis have both used strong language pertaining to North Korea's threats.
Trump's comments were his first since North Korea reacted to his "fire and fury" threat by announcing a detailed plan to launch a salvo of ballistic missiles toward the U.S. Pacific territory of Guam, a major military hub and home to U.S. bombers. But the progress it has made has unnerved much of Asia, prompting a new set of sanctions by the United Nations Security Council.
China's foreign ministry said in a statement that Mr Xi told Mr Trump a peaceful resolution to the North Korean nuclear issue was essential, and urged calm.
Although Guam remains on alert, Gov. Eddie Baza Calvo took pains to assure residents on Wednesday that there was no immediate danger.
North Korea's apparently rapid progress in developing nuclear weapons and missiles capable of reaching the USA mainland has fuelled tensions that erupted into a war of words between Washington and Pyongyang this week, unnerving regional powers and global investors.
People familiar with the contacts say the interactions have done nothing thus far to quell tensions over North Korea's nuclear weapons and missile advances, which are now fueling fears of military confrontation.
"Sound dialogue is not possible with such a guy bereft of reason and only absolute force can work on him", a report by the North's state-run KCNA news agency said of Trump.
Guam preps citizens on how to survive a nuclear attack
Japan's government made a decision to deploy its Patriot missile defence system to four locations in the west of the country, media reported.
The White House said Mr Trump reiterated the USA commitment to stop the "North Korean nuclear menace" and said Washington was ready with diplomatic, economic and military measures.
"It may very well be tougher than I said".
The North then came out with a threat to lob four intermediate-range "Hwasong-12" missiles near Guam, a tiny USA territory some 3,200 kilometers (2,000 miles) from Pyongyang.
"I think escalating the rhetoric is the wrong answer", Merkel added. "We are with you a thousand percent".
USA officials have said new U.S. steps that would target Chinese banks and firms doing business with Pyongyang are in the works, but these have appeared to be put on hold to give Beijing time to show it is serious about enforcing new United Nations sanctions.