The United States and North Korea are planning a third summit to discuss the future of North Korea’s nuclear program, after months of lull in negotiations.

South Korean President Moon Jae-in confirmed that informal talks between President Trump and North Korean dictator Kim Jong Un are ongoing, according to the Wall Street Journal. No date has been set.

Trump signaled openness to a third summit in April, tweeting that his relationship with the North Korean leader remains "very good, perhaps the term excellent would be even more accurate."

U.S. negotiators are pushing North Korea to implement a verifiable denuclearization program before the U.S. will relax sanctions. North Korea wants a piecemeal approach by both sides.

North Korea has grown increasingly frustrated with the pace of negotiations, test-firing short-range missiles into the Sea of Japan and openly slamming the U.S. in state-run media.

"The wild dream of the U.S. to bring us to our knees by means of sanctions and pressure has not changed at all but grows even more undisguised," North Korean state media said on Wednesday.

Trump and Kim last met in February in the Hanoi, Vietnam. That summit ended in embarrassment for both leaders, ending early as the two sides failed to come to an agreement.

"Sometimes you have to walk. And this was just one of those times," Trump said at the time.

The U.S. State Department did not immediately respond to a request for comment.