South Korea's deployment of a U.S. missile defence system loathed by Beijing will also be high on Mr Wu's agenda, Yonhap news agency said. "So the president has asked us to be prepared to give him a full range of options to remove that threat to the American people and our allies and partners in that region".

During a 45-minute phone conversation proposed by Washington following a two-day meeting between Trump and Chinese President Xi Jinping in Florida, Abe also told Trump that Tokyo is watching closely how China responds to the issues, the Japanese leader told reporters.

"Presidents before and Mr Trump agreed that that is unacceptable, and that what must happen is the denuclearisation of the peninsula", US National Security Adviser H.R. McMaster told Fox News on Sunday.

Before the meeting at his Mar-a-Largo estate, Trump was reportedly presented with options to respond to the North's nuclear weapons program including placing USA nukes in South Korea or assassinating North Korean leader Kim Jong Un. It has staged five nuclear tests so far and could be preparing a sixth.

The U.S. launched 59 Tomahawk missiles Thursday night against the Syrian air base where Bashar Assad's government had days earlier fired off a devastating chemical weapon attack that left more than 85 people in the town of Khan Sheikhoun dead.

Adm. Harry Harris, commander of U.S. Pacific Command, directed the Nimitz-class supercarrier USS Carl Vinson and its accompanying ships, including two guided-missile destroyers and a guided-missile cruiser, to sail north to the Western Pacific from Singapore on Saturday, instead of heading for Australia as originally scheduled.

For North Korea, cutting off oil supplies would be devastating
About 200 reporters are in Pyongyang to cover the event, including journalists from the US and Japan . Trump said China would get a better trade deal if it reined in its troublesome ally.

"Third Fleet ships operate forward with a goal: to safeguard U.S. interests in the Western Pacific", Commander Dave Benham, Director of Media Operations for the U.S. Pacific Command Third Fleet, told VOA.

Among the topics of discussion was the vexing problem of North Korea.

Pyongyang has repeatedly defied worldwide warnings about conducting missile launches and testing nuclear devices.

South Korea's Ministry of National Defense said Monday that the deployment of the strike group shows that the United States "recognizes the seriousness of the situation on the Korean Peninsula".

"Those are the kinds of steps that the United States could take alone or with other countries, that don't include China, that are directed at North Korea but that China wouldn't like", said Blinken, adding if the threat from North Korea continues to grow, "if necessary, those are things that I would recommend doing".