WASHINGTON (BLOOMBERG/AFP) - US President Donald Trump on Monday said he would not rule out meeting North Korean leader Kim Jong Un, saying he would be "honoured to do it", despite weeks of tough talk against the regime.

"If it would be appropriate for me to meet with him I would absolutely. I would be honoured to do it," Trump said in an interview with Bloomberg.

Tensions with North Korea have soared in recent weeks, amid Pyongyang's series of provocative missile tests.

The Trump administration has repeatedly warned "all options are on the table" when it comes to dealing with North Korea's missile and nuclear programs - but it also stressed last week it is open to direct talks with Pyongyang.

"If it's under the, again, under the right circumstances. But I would do that," Trump said.

Kim's regime has continued development of its nuclear and intercontinental ballistic missile program in defiance of international condemnation and sanctions. Kim has never met with a foreign leader since taking charge after his father's death in 2011 and hasn't left his isolated country.

"Most political people would never say that," Trump said of his willingness to meet with the reclusive Kim, "but I'm telling you under the right circumstances I would meet with him. We have breaking news."

Tensions have escalated since Trump vowed in January that he wouldn't let North Korea develop a nuclear weapon capable of reaching the US mainland, and North Korea has labelled American military moves in the region as acts of "intimidation and blackmail".

North Korea has continued to test missiles this year after carrying out its fourth and fifth nuclear tests in a decade last year.

While dispatching an aircraft carrier group and a submarine to the region, the administration has emphasised the use of economic sanctions and diplomacy to persuade North Korea to dismantle its nuclear weapons and missile programmes.

Trump has said he's leaning on Chinese President Xi Jinping to defuse the situation, given China's economic influence with its neighbour. Trump and Xi met last month at the U.S. president's private club in Florida and have talked several times since.

Then-Secretary of State Madeleine Albright was the last top US official to meet with a North Korean leader. She discussed the country's nuclear program with Kim's father, Kim Jong Il, in 2000. At the time, she was the most senior official to visit the Stalinist state in the 50 years since the Korean War.