WASHINGTON — President Donald Trump agreed on Thursday to a historic first meeting with Kim Jong Un in a stunning development in America’s high-stakes nuclear standoff with North Korea.

Standing in front of the White House, South Korean National Security Advisor Chung Eui-yong earlier announced the first ever meeting between a US president and North Korean leader, which he said would take place by the end of May.

Chung had recently returned from Pyongyang, where he met Kim personally.

According to the South Korean official, the reclusive young leader "expressed his eagerness to meet president Trump as soon as possible."

Trump confirmed he had agreed to meet Kim -- hailing "great progress" in the push to persuade Pyongyang to end its nuclear programme.

"Meeting being planned!" Trump tweeted. "Kim Jong Un talked about denuclearisation with the South Korean Representatives, not just a freeze. Also, no missile testing by North Korea during this period of time."

"Great progress being made but sanctions will remain until an agreement is reached."

The news came almost out of the blue, after a period of extreme tension and bellicose rhetoric between Washington and Pyongyang that sounded like the growing drumbeat of war.

The United States and North Korea were foes throughout the Cold War and fought on the opposite side of a bloody war in the 1950s.

In the last two decades, they have been engaged in what is perhaps the world’s most dangerous nuclear standoff, with 30,000 US military personnel stationed just over the border in the South.

Pyongyang’s recent race to develop a nuclear weapon capable of hitting the continental United States prompted Trump to embark on a campaign of sanctions, diplomatic pressure and the threat of military force.

The White House said that strategy of "maximum pressure" would stay in place, for now.

"We look forward to the denuclearization of North Korea. In the meantime, all sanctions and maximum pressure must remain."

But the prospect of a top-level meeting is nothing short of a paradigm shift.

North Korean leaders have sought face-to-face talks with consecutive US presidents, who have rebuffed the notion as an effort to achieve strategic parity that does not exist.

Pyongyang now seems to have achieved its goal, while only agreeing to a temporary suspension of nuclear tests.

The table was set for the announcement on Tuesday when South Korea shocked the world by announcing that the North had stated there was "no reason" to hold on to its nuclear weapons "if military threats towards the North are cleared and the security of its regime is guaranteed."

The North is open to "frank" talks with the United States on denuclearisation and would suspend missile and nuclear tests while dialogue was under way, Chung said after returning from a meeting in Pyongyang.

Seoul also announced the two Koreas would hold a historic summit in the Demilitarised Zone next month -- and that the North’s leader Kim Jong Un was ready to halt provocative missile and nuclear tests and sit down with its old enemies.

Trump had welcomed the offer as "very positive" and refused to rule out a meeting with Kim.

"We have come a long way at least rhetorically with North Korea," Trump said. — AFP