Top North Korean to hand-deliver letter to Trump from Kim Jong Un: Pompeo

President Donald Trump signaled Thursday that it’s very likely a delegation of North Korean officials “will probably be coming down” to Washington Friday to hand-deliver a letter to him from Kim Jong Un.

Trump said he doesn’t know what the letter will say but says he thinks “it’ll be very positive.”

Later Thursday, Secretary of State Mike Pompeo confirmed that Kim's top adviser, Kim Yong Chol, would deliver the letter himself after talks with Pompeo in New York.

Trump cautioned that while he hopes a planned summit in Singapore on June 12 between the U.S. and North Korea is still in the cards, he wants it to be a “meaningful” meeting.

“That doesn't mean it gets all done at one meeting, maybe you have to have a second or a third and maybe we'll have none, but it's in good hands, that I can tell you,” Trump said.

Trump made the remarks ahead of a day trip to Dallas, where he plans to attend private fundraisers and meet with the families of the Santa Fe High School shooting victims.

Less than a week after the president "canceled" the summit in a dramatic letter, there's been a flurry of activity between the two countries to make it happen again. There was never an official "back on" message, but Trump tweeted Tuesday that his letter got a "solid response."

The point person for U.S. preparations, Secretary of State Mike Pompeo, met with Kim Yong Chol, a top adviser to Kim Jong Un and vice chairman of the Central Committee Wednesday. It's the third meeting between the two men, after Pompeo's two trips to Pyongyang in as many months.

North Korea has denied any interest in U.S. economic assistance, only in ending international sanctions – and on Thursday, the real challenge of negotiating differences begins with a full day of meetings between the two delegations.

Kim Yong Chol is the regime's former spy chief and reportedly behind some of its most malicious behavior, including assassination attempts in South Korea, the sinking of a South Korean navy ship and the Sony hack. He is currently under U.S. sanctions, so the U.S. had to grant him a special waiver to travel to New York.

ABC News' Conor Finnegan and Alex Mallin contributed to this report.