The US administration thinks China's economic leverage over North Korea is the key to strong-arming Pyongyang into halting its nuclear weapons and missile programmes.
On Friday he warned world leaders gathered in the Vietnamese resort city of Danang that the Asia-Pacific region "must not be held hostage to a dictator's twisted fantasies".
A spokesman for North Korea's foreign ministry published a lengthy and incendiary commentary, condemning Trump for a "warmonger's visit" with the goal of ending the nation's effort to create a "self-defensive" nuclear weapons program.
North Korea has dominated Mr Trump's Asia trip so far to Japan, South Korea, China and Vietnam.
He called on nations to stop financing and trading with North Korea.
Iran Urges France to Make Regional Allies Opt for Rationality
Trump and his administration have accused Iran of using the ballistic missile program to further development of its nuclear weapons.
The South Morning China Post quoted military officials describing this as a clear warning to North Korea, which involve three US aircraft carriers.
At the meeting, the two countries agreed to deepen their cooperation on North Korea and to hold a trilateral summit with South Korea at the earliest possible date.
The USS Ronald Reagan, USS Nimitz and USS Theodore Roosevelt strike groups operated together, marking the first time three American aircraft carriers have trained together since 2007, according to the U.S. Pacific Fleet which released a video of the training on Sunday.
During Saturday's summit, Moon and Xi also agreed to quickly normalise bilateral exchanges in all sectors, reiterating an agreement announced last month to end a year-long standoff over the deployment of a USA anti-missile system.
It marks the first time that the country's Navy has conducted a combined training with three USA aircraft carriers.
SoCal Theme Park Shuts Towers Linked to Legionnaires' Disease
Each year, an estimated 10,000 to 18,000 people in the United States are infected with this bacteria. It is treated with antibiotics, which can improve symptoms and shorten the length of illness.
The region, he added, must "stand united in declaring that every single step the North Korean regime takes toward more weapons is a step it takes into greater and greater danger".
Vietnam has eagerly courted trade and investment with the USA since Trump's election, more so after he yanked the United States from a key Pacific region trade pact, taking with him low tariff access to the world's largest market.
Tensions have been running high since North Korea test-fired two intercontinental ballistic missiles in July, conducted its sixth and most powerful nuclear test on September 3 and flew ballistic missiles over Japan on August 29 and September 15.
It also flew two new midrange missiles over Japan and threatened to launch them toward Guam, a US Pacific territory and military hub.
Restaurants Offering Free Meals For Retired, Active Military On Veterans Day
Ruby Tuesday (Concord, Nashua and Portsmouth): Former and active duty service members receive a free appetizer Saturday, Nov. 11. Stop by any Denny's and Military personnel will get a free Build Your Own Grand Slam on Friday , November 10th, 2017.