President Donald Trump said he had walked away from a nuclear deal at his summit with Kim Jong Un in Vietnam on Thursday because of unacceptable demands from the North Korean leader to lift punishing U.S.-led sanctions.

Trump said two days of talks in the Vietnamese capital Hanoi had made good progress in building relations and on the key issue of denuclearization, but it was important not to rush into a bad deal.

Kim wanted sanctions to be “lifted in their entirety and we wouldn’t do that,” the president said.

President Donald Trump and North Korean leader Kim Jong Un failed to reach a nuclear agreement during their second summit, which was abruptly cut short in Hanoi, Vietnam on Thursday afternoon.

Speaking to reporters following his negotiations with Kim, Trump said there were two sticking points that had made a deal “inappropriate” at this time. Kim wanted sanctions to be “lifted in their entirety and we wouldn’t do that,” the president said.

President Donald Trump opened an historic second summit with Kim Jong Un here Wednesday by pledging to push for North Korean denuclearization, even as he faced a political firestorm at home that threatens to eclipse any progress.

The president has sold Kim Jong Un on peace and prosperity. But North Korea's record on human rights stands in the way.

President Donald Trump and North Korea’s Kim Jong Un hold a second summit this week with no real expectation of a final deal on ridding the North of nuclear weapons but hope raised on Monday for an official peace on the peninsula at long last.

This time around, President Trump faces higher expectations.

His intelligence chiefs warn that North Korea is unlikely to surrender its nuclear weapons. His advisers fret that a breakthrough could prove elusive and that he might make an impulsive concession to score headlines. And his allies around the world worry he could get easily outmaneuvered.

Even by the combustible standards of Donald Trump, the spectacle set to unfold around his presidency in time zones 12 hours apart in the next few days could defy description.

President Donald Trump arrives in Hanoi, Vietnam, Tuesday for the two-day follow-up summit with North Korean dictator Kim Jong Un. He's still pressing for the regime to get rid of its nuclear weapons but says he's made great progress since the first summit last year.