His tweets came shortly after Air Force One landed at Joint Base Andrews just outside Washington.
Mr Trump’s assessment comes as lawmakers, analysts and allies have hailed the effort, but questioned the substance of what was achieved.
A brief document signed by Trump and Kim provided virtually no detail beyond the stated commitment to “denuclearise,” a promise that Pyongyang has made and ignored many times in the past.
North Korea is believed to possess more than 50 nuclear warheads, with its atomic program spread across more than 100 sites constructed over decades to evade international inspections.
Even as they offered measured praise for Mr Trump’s diplomatic efforts, congressional Republicans have emphasised the difficult road that remains and pressed for more details of what exactly the President agreed to with Kim.
Senator Bob Corker said on Tuesday that he wanted Secretary of State Mike Pompeo to brief senators on the substance of what the two nations discussed, including whether US troops stationed on the Korean Peninsula would remain.
“I have no idea” whether Trump secured anything of substance, Senator Corker, the retiring chairman of the Senate Foreign Relations Committee said.
“At this juncture, I don’t think we know enough to challenge or celebrate.”
In his tweets, Mr Trump called his meeting with Kim “an interesting and very positive experience”.
He also said that before he took office last year, “people were assuming that we were going to War with North Korea”.
“President Obama said that North Korea was our biggest and most dangerous problem. No longer – sleep well tonight!” the President wrote.
Donald Trump and Kim Jong-un were returning to their respective strongholds following the talks _ but to far different receptions.
In Pyongyang, the North Korean autocrat woke up to state media’s enthusiastic claims of a victorious meeting with the US President; photos of him standing side-by-side with Trump on the world stage were splashed across newspapers.
Mr Trump, meanwhile, faced questions about whether he gave away too much in return for far too little when he bestowed a new legitimacy on Kim’s rule and agreed, at Pyongyang’s request, to end war games with Seoul that the allies had long portrayed as crucial to Asian safety.
As US Secretary of State Mike Pompeo flew to South Korea for follow-up talks on Wednesday, much of Asia was still trying to process the whirlwind events of the day before.
There was, at times, a surreal quality to the carefully staged, five-hour meeting of two men who had been threatening each other with nuclear war and insulting each other’s mental and physical attributes just months before.
Mr Trump repeatedly praised Kim’s negotiating skills and their new relationship and expressed hope for “a bright new future” for Kim’s impoverished nation.
But there were worries, especially in Tokyo and Seoul, which both have huge US military presences, about Mr Trump agreeing to halt US military exercises with South Korea, which the North has long claimed were invasion preparations. That concession to Kim appeared to catch the Pentagon and officials in Seoul off guard, and some South Koreans were alarmed.
“The United States is our ally, so the joint military drills are still necessary to maintain our relationship with the US,” said Lee Jae Sung, from Incheon. “I think they will be continued for a while.”
In Japan, the prospect of canceled US-South Korean drills was met with concern.
“The US-South Korea joint exercises and US forces in South Korea play significant roles for the security in East Asia,” Japanese Defense Minister Itsunori Onodera told reporters Wednesday. He said he planned to continue sharing the view with Washington and Seoul.
The US has stationed combat troops in South Korea since the end of the Korean War in the 1950s and has used them in a variety of drills. The next scheduled major exercise, involving tens of thousands of troops, normally is held in August.
The Pentagon said on Tuesday that it was consulting with the White House and others, but was silent on whether the August exercise would proceed.
Mr Pompeo arrived at Osan Air Base south of Seoul from Singapore early on Wednesday evening and met for close to an hour with General Vincent Brooks, commander of US Forces Korea, at the air base before heading by motorcade to Seoul.
Mr Pompeo will meet President Moon Jae-in on Thursday morning to discuss the summit. Japanese Foreign Minister Taro Kono is also heading to Seoul and is due to meet with Mr Pompeo and his South Korean counterpart. Mr Pompeo, the former CIA director, then plans to fly to Beijing to update the Chinese government on the talks.
Despite the confusion and disappointment among some, the summit managed to, for a time at least, reset a relationship that has long been characterised by bloodshed and threats.
In agreeing to the summit, Mr Trump risked granting Kim his long-sought recognition on the world stage in hopes of ending the North’s nuclear program.
Mr Trump insisted that strong verification of denuclearisation would be included in a final agreement, saying it was a detail his team would begin sorting out with the North Koreans next week.
Washington Post with AAP
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