U.S. President Donald Trump has suggested that he has developed a positive relationship with North Korean leader Kim Jong-un, but declined to say whether they have spoken. 

Trump on Thursday made the suggestion during an interview with the Wall Street Journal.

Asked if he had spoken with Kim, Trump refused to elaborate, saying that "I'm not saying I have or haven't. I just don't want to comment."  

He also said that "You'll see that a lot with me," referring to the difference between his friendly tone towards Kim and his previous harsh comments against him.

Trump said that all of a sudden somebody becomes his best friend and he could give 20 or 30 examples, adding he is a "very flexible person.”

These remarks come after the two Koreas this week held their first talks in two years, and the North agreed to participate in the Winter Olympics in the South next month.

The WSJ said that the remarks hint that Trump is open to diplomatic solutions to the North Korean nuclear issue.