President Trump gave a shout-out Sunday to North Korean leader Kim Jong-un, referring to their “[g]reat relationship” and touting the economic benefits of denuclearization for the communist nation.

“Great relationship with Chairman Kim!” tweeted Mr. Trump.

The president’s comments came ahead of the much-anticipated second summit aimed at curbing North Korea’s nuclear weapons program, with talks scheduled to start this week in Hanoi.

Chairman Kim realizes, perhaps better than anyone else, that without nuclear weapons, his country could fast become one of the great economic powers anywhere in the World. Because of its location and people (and him), it has more potential for rapid growth than any other nation! — Donald J. Trump (@realDonaldTrump) February 24, 2019

President Xi of China has been very helpful in his support of my meeting with Kim Jong Un. The last thing China wants are large scale nuclear weapons right next door. Sanctions placed on the border by China and Russia have been very helpful. Great relationship with Chairman Kim! — Donald J. Trump (@realDonaldTrump) February 24, 2019

Very productive talks yesterday with China on Trade. Will continue today! I will be leaving for Hanoi, Vietnam, early tomorrow for a Summit with Kim Jong Un of North Korea, where we both expect a continuation of the progress made at first Summit in Singapore. Denuclearization? — Donald J. Trump (@realDonaldTrump) February 24, 2019

Mr. Trump also said Saturday’s talks with China on trade were “very productive.” The U.S. and Chinese delegations are slated to meet again today to hammer out an agreement before March 1, after which the president has said he will hike tariffs on Chinese goods unless a deal is reached.