Pompeo met the North Korean leader earlier this month to discuss possible direct talks between Trump and Kim.

CIA Director Mike Pompeo held a secret meeting with Kim Jong-un in North Korea earlier this month in what is believed to be the highest-level meeting between the two countries in nearly two decades.

The “meeting went very smoothly and a good relationship was formed”, US President Donald Trump said on Twitter on Wednesday.

“Details of Summit are being worked out now. Denuclearization will be a great thing for World, but also for North Korea!” Trump added.

Mike Pompeo met with Kim Jong Un in North Korea last week. Meeting went very smoothly and a good relationship was formed. Details of Summit are being worked out now. Denuclearization will be a great thing for World, but also for North Korea! — Donald J. Trump (@realDonaldTrump) April 18, 2018

US media reported that Pompeo made the trip shortly after being named Trump’s pick to replace Rex Tillerson as secretary of state.

Pompeo and Kim discussed the planned summit between US and North Korea leaders.

Earlier on Tuesday, Trump had said that the US was engaged in direct talks at “extremely high levels” with Pyongyang.

White House Press Secretary Sarah Sanders clarified Trump’s comments, saying “the president said the administration has had talks at the highest levels and added that they were not with him directly”.

When asked about Pompeo, Sanders said: “The administration does not comment on the CIA director’s travel.”

‘Optimistic’ about Trump-Kim summit

After the trip, Pompeo told the administration that it was worth continuing to look at the possibility of a summit, the Reuters news agency reported, citing two US officials.

Pompeo addressed the Trump-Kim summit during a Senate confirmation hearing for secretary of state this week.

“I’m optimistic that the United States government can set the conditions for that appropriately so that the president and the North Korean leader can have that conversation [that] will set us down the course of achieving a diplomatic outcome that America so desperately – America and the world so desperately need,” Pompeo said at the hearing with the Senate Foreign Relations Committee.

Pompeo’s meeting with Kim constituted the highest-level talks between North Korea and the US since 2000 when then-Secretary of State Madeleine Albright met Kim’s father, Kim Jong-il.

The US does not have formal diplomatic relations with North Korea.

Trump accepted an invitation in March to meet Kim this summer.

The invitation followed months of diplomatic standoff that saw the two leaders exchange fiery military threats and personal insults.

Also on Tuesday, Trump gave his “blessing” for inter-Korean talks, scheduled for April 27.

“Subject to a deal they have my blessing and they do have my blessing to discuss that,” Trump said.