US President Donald Trump said on Thursday (May 31) talks with North Korea in New York have been very positive and he is expecting the delegation from Pyongyang to travel to Washington on Friday to deliver a letter to him from leader Kim Jong Un.

Trump said he was hopeful his summit with Kim would take place on June 12 as originally scheduled but left open the possibility talks would fall through.

"I look forward to seeing what's in the letter," Trump said as he left Joint Base Andrews for a trip to Houston. Asked if a deal was taking shape, Trump said: "I think it will be very positive. ... The meetings have been very positive."

Kim and Trump were supposed to meet in Singapore on June 12. But Trump canceled the summit on May 24, before backtracking a day later and saying that the meeting could still happen according to the initial schedule.