Trump also linked the move to his growing spat with Beijing, which has roiled financial markets and global commerce.
Tokyo is also pushing hard to resolve the sensitive issue of Japanese abducted by North Korea.
North Korea accused the US of having "double-dealing attitudes".
In addition, recent statements from North Korean officials have ruled out any new concessions until it sees a reciprocal gesture from the USA beyond suspending military exercises with South Korea.
The problem, experts said, is that the trade dispute isn't likely to be solved soon.
The planned trip had been planned for this week and was announced last week.
And he suggested China was not doing enough to pressure North Korea - due to trade tensions with the US.
Beijing, which accounts for more than 90 percent of North Korea's trade, complied by suspending coal and textile imports among other measures.
The U.S. military called the accusations "far fetched". North Korea admitted in 2002 it had kidnapped 13 Japanese in the 1970s and 1980s to train as spies, and five of them returned to Japan.
"The United States has once again stressed its commitment to the full and verified denuclearization of the Korean Peninsula".
Prince Harry & Meghan Markle Reportedly Adopted A Dog Together
Meghan is a known dog-lover, and regularly posted pics of Guy and Bogart to her Instagram, back when she was allowed to have one. Britain's Prince Harry and Meghan the Duchess of Sussex arrive at a charity polo match in Windsor, Britain, July 26, 2018.
The Donald dramatically called off Secretary of State Mike Pompeo's visit to the Hermit Kingdom after the official sent the letter.
The United States is pressing North Korea to give up its nuclear weapons program, calling for stringent implementation of tough USA and U.N. sanctions.
However, it is unclear what exercises North Korea was referring to.
"Good decision especially if otherwise Pompeo would have returned empty handed", Hill said in a tweet.
Kawasaki, 76, who was born in Japan and lived for 43 years in North Korea before defecting, has not seen her children, still in North Korea, for years. China also has been allowing more Chinese tourists to visit North Korea this year as relations between the two countries have improved significantly.
But there has been no indication that North Korea had stopped its nuclear activities, the International Atomic Energy Agency (IAEA) said in a report on Monday.
Although it has halted nuclear and missile testing and taken some unrelated steps - dismantling portions of a missile engine facility and returning the suspected remains of American servicemen killed during the Korean War - its nuclear weapons program and ballistic missile development remain intact, according the U.N.'s atomic watchdog and intelligence agencies.
Shim said he was able to meet with his younger brother living in North Korea in the Chinese border town of Yanji in 1994 after a Chinese helper disguised himself as his brother's uncle and invited him to visit.
The second round is scheduled to be held across six sessions over three days, totalling 12 hours of meetings.
There has been no confirmation that the third-generation North Korean leader will attend the global meeting. Trump "overplayed the gains" from his Singapore summit with North Korean leader Kim Jong Un and needed someone else to blame, Lee said.