The U.S. and North Korea are engaged in secret and direct talks to prepare for a summit between President Donald Trump and North Korean leader Kim Jong Un, CNN reported Saturday.

Central Intelligence Agency Director Mike Pompeo, who Trump has tapped to be secretary of the State Department, has been working through intelligence back-channels to prepare for the summit. Should Pompeo be confirmed as State Department secretary, he will oversee the diplomatic preparations.

Officials from the U.S. and North Korea have spoken several times and even met in a third country, with the first intention of deciding a date to hold the talks.

The invitation extended to Trump by Kim was originally conveyed through a South Korean envoy. Though North Korea has refrained from publicly announcing the invitation, officials say North Korea has said Trump has accepted. The North Koreans have reaffirmed Kim is willing to talk about denuclearization of the Korean Peninsula, CNN reported.

North Koreans officials have indicated they wanted to hold the summit in their capital of Pyongyang, sources said. It is not certain Trump would be willing to meet there, and the Mongolian capital of Ulaanbaatar has also been mentioned as a possibility.

Talks are underway for Pompeo to first meet with his North Korean counterpart. Once they agree upon a location for the summit, officials will then work on targeting a date and setting the agenda for the talks.

Trump told associates he is looking forward to meeting with Kim, CNN reported. Officials are eyeing late May or June for the summit to take place.

Japanese Prime Minister Shinzo Abe is expected to deliver to Trump a list of concerns about beginning a dialogue with Kim in a meeting with the president in two weeks. The Chinese also have given the White House a briefing of a meeting between President Xi Jinping and Kim last month.

U.S. government agencies preparing for the summit are being led by Matthew Pottinger, the top Asia official at the National Security Council. Former U.S. Ambassador to the U.N. John Bolton, who will start his new position as Trump's national security adviser on Monday, is expected to play a role in the talks along with Pompeo.

State Department officials are also working on preparations for the summit, including a review of previous negotiations with North Korea.

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