President Donald Trump said he hopes the escalating tensions with North Korea can be resolved "in a peaceful way," but warned that "it's very possible that it can't."

Trump made his remarks on North Korea and its leader, Kim Jong Un, in an Oval Office interview with Reuters on Wednesday.

With North Korea persisting as the major global challenge facing Trump this year, the president cast doubt during the 53-minute interview on whether talks with North Korean leader Kim Jong Un would be useful. In the past he has not ruled out direct talks with Kim.

"I'd sit down, but I'm not sure that sitting down will solve the problem," he said, noting that past negotiations with the North Koreans by his predecessors had failed to rein in North Korea's nuclear and missile programs.

"They've talked for 25 years and they've taken advantage of our presidents, of our previous presidents," he said.

He declined to comment when asked whether he had engaged in any communications at all with Kim, with whom he has exchanged public insults and threats, heightening tensions in the region.

Trump said he hoped the standoff with Pyongyang could be resolved "in a peaceful way, but its very possible that it can't."

Trump praised China for its efforts to restrict oil and coal supplies to North Korea but said Beijing could do much more to help constrain Pyongyang.

The White House last week welcomed news that imports to China from North Korea, which counts on Beijing as its main economic partner, plunged in December to their lowest in dollar terms since at least the start of 2014.