Donald Trump and Kim Jong-un have cut short their talks in Hanoi, Vietnam and skipped a scheduled lunch event.
The White House confirmed the summit had ended with “no agreement reached” as the leaders headed back to their respective hotels.
The US president talks broke down over North Korea’s demands on US-led sanctions.
“Basically, they wanted the sanctions lifted in their entirety, but we couldn’t do that,” he told reporters. “Sometimes you have to walk.”
Sarah Sanders, the White House press secretary, said negotiations would continue at a future date.
Several Democrats came out acknowledging Mr Trump’s decision to walk away without a deal was the right move in this situation. Democratic Congressman Adam Schiff said walking away with no deal was better than agreeing to a bad deal, before adding that it was “the result of a poorly planned strategy.”
Senate Minority Leader Chuck Schumer echoed similar statements, citing his concerns about the likelihood of a bad deal forming out of the summit.
“A deal that fell short of complete denuclearization would have only made North Korea stronger & the world less safe,” Mr Schumer said.
After the summit, Mr Trump also defended Mr Kim over the tragic death of American college student Otto Warmbier, who was jailed in North Korea in December 2015 for attempting to steal propaganda material during an organised tour.The president said he does not believe the autocratic leader was aware of Mr Warmbier’s condition in the North Korean hard labour prison camp.
"He tells me he didn't know about it, and I will take him at his word,” Mr Trump said.
After two years of imprisonment, North Korean authorities returned Mr Warbier to the US in a coma in July 2017. A few days later, the 22-year-old died in his hometown of Cincinnati, Ohio.
Ohio Senators Sherrod Brown and Rob Portman criticised the American president’s defense of Mr Kim.
“I’m very concerned that the President didn’t seem to be all that concerned about the murder of Otto Warmbier from Cincinnati,” Mr Brown told reporters on Thursday. “I don’t know how he says he likes the dictator of NK so much.”
Mr Portman insists that Mr Trump and the American people must remember Mr Warmbier and that “we should never let North Korea off the hook for what they did to him."
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Tuesday's vote in the Democratic-controlled House comes on legislation to revoke Trump's executive order from earlier this month and would send it to the Republican-held Senate, where it would take only a handful of defections to pass.
President Trump is likely to prevail in the end since he could use his first-ever veto to kill the measure if it passes Congress but the White House is seeking to minimise Republican support for the measure to avoid such an embarrassment.
The vote could be challenging for conservative lawmakers who view themselves as protectors of the US Constitution and the powers of the federal purse that are reserved for Congress. But the party's vote counters are confident the tally won't get near the two-thirds that would overturn a Donald Trump veto.
"The beauty of the Constitution, the heart and soul of the Constitution, is the separation of power - co-equal branches of government to be a balance of power," said House Speaker Nancy Pelosi. "The Constitution spells out the responsibilities, giving the Congress of the United States, among other powers, the power of the purse. The president's power grab usurped that constitutional responsibility and fundamentally violates the balance of power envisioned by our founders."

President Trump took to Twitter on Monday to urge Senate Republicans to stick with him:
Vice-president Mike Pence is expected to discuss the issue with Republican senators during their weekly private lunch. A Justice Department official is also expected to attend.
On Monday, North Carolina senator Thom Tillis became the second Republican senator, joining Alaska's Lisa Murkowski, to say he would vote to block the order. Congress must defend its power of the purse and warned that a future Democratic president might abuse the power to advance "radical policies," Senator Tillis said.
At issue is President Trump's longstanding vow to build a wall along the 2,100-mile southwestern border, his signature campaign promise. He has long since dropped any pretense that money for the wall would come from Mexico, which he initially loudly claimed would be the source of funding.
Earlier this month, Congress approved a huge spending bill providing nearly $1.4bn (£1.1bn) to build 55 miles of border barriers in Texas's Rio Grande Valley, ending a dispute that had led to a record 35-day partial shutdown of the government.
"We are aware of no emergency that remotely justifies such a step," wrote 58 former senior national security officials, including Republican Chuck Hagel, a former Nebraska senator and defense secretary. "Under no plausible assessment of the evidence is there a national emergency today that entitles the President to tap into funds appropriated for other purposes to build a wall at the southern border."
In addition, 28 Republican former House members and senators, many of them from the party's shrinking moderate wing, wrote an open letter declaring their opposition to Trump's emergency declaration.
"How much are you willing to undermine both the Constitution and the Congress in order to advance a policy outcome that by all other legitimate means is not achievable?" wrote the former Republican lawmakers, among them former Senator Richard Lugar, once the chairman of the Senate Foreign Relations Committee.
"It was a lawless act, a gross abuse of power, and an attempt to distract from the fact that he broke his core promise — to have Mexico pay for the wall," said top Senate Democrat Chuck Schumer of New York.
Mr Trump's edict is also being challenged in the federal courts, where 16 Democratic-led states such as California are among those that have sued to overturn the order. The House may join in.


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The president has been accused by dozens of women of sexual misconduct. Mr Trump has denied those allegationsAs FBI special counsel Robert Mueller nears the end of a 21-month probe into whether the Kremlin meddled in the 2016 presidential election in collusion with the Trump campaign (an accusation denied by both camps), Cohen is set to offer lawmakers new information about the president's private affairs over the three consecutive days.
He is also expected to give lawmakers "granular details" about Mr Trump's $130,000 (£98,540) hush-money payments to adult film actress Stephanie Clifford, known as Stormy Daniels, in exchange for her silence about an alleged extramarital affair with the real estate magnate turned statesman.
In addition, Cohen will offer new information on Trump's financial statements that "have never been produced before" relating to how Mr Trump represented the values of his assets in financial transactions and other matters, said the source.
Cohen pleaded guilty on 29 November last year to criminal charges including tax evasion, bank fraud and campaign finance violations. In December, he was sentenced to three years in prison for crimes including orchestrating payments to Ms Daniels and Playboy model Karen McDougal in violation of campaign laws before the 2016 election.
The New York lawyer once said he would "take a bullet" for his employer but has since turned against him. When Cohen pleaded guilty to campaign finance violations, he implicated the president, who afterward called him a "rat" on Twitter.
Possible conflicts of interest faced by Mr Trump, including at his Trump International Hotel in Washington, will be targets for the Cummings panel, as will the Trump Foundation and "efforts by the president and his attorney to intimidate Mr. Cohen or others not to testify," the committee said.

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Also on the platform is Hyon Song-wol, a North Korean ruling party elite and the leader of the famous girl band Moranbong. Hyon's inclusion in Mr Kim's delegation has raised speculation that cultural events could be part of the agreements reached between Washington and Pyongyang this week as they look for easier steps to improve relations.
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