CIA Director Mike Pompeo traveled to North Korea over Easter weekend for a meeting with leader Kim Jong Un, sources confirmed to CNN on Tuesday.
One source said Pompeo took only intelligence officials with him on the trip, no White House or State Department officials.
The meeting between Pompeo and Kim comes ahead of a planned historic summit between the North Korean leader and US President Donald Trump, currently planned for sometime in late May or early June.
It will be the first official meeting between a member of the ruling Kim family and a sitting United States president.
The White House declined to comment on Pompeo's visit after The Washington Post, citing two sources with direct knowledge of the trip, reported that Trump's nominee for secretary of state had made the top-secret visit as an envoy for Trump.
News of the secret meeting broke as Trump hosted a visit with Japanese Prime Minister Shinzo Abe in Florida.
Trump confirmed Tuesday while alongside Abe that the US and North Korea are having discussions at "very high levels" in preparation for an anticipated meeting between Trump and Kim.
"We have had direct talks," the President said. The White House later clarified Trump's comments to make it clear he has not yet talked directly with Kim.
Speaking to reporters on Tuesday, Trump said there were five locations being considered for the historic summit but didn't elaborate on what they might be.
It is just over a week until South Korean President Moon Jae-in is due to meet with Kim in the demilitarized zone between the two countries, the first meeting between the two countries' leaders in a decade.
Moon is widely viewed as the main proponent of diplomatic talks between North Korea, South Korea and the United States.
The former CIA director's trip to North Korea around April 1, the date of Easter Sunday, came amid a major shakeup in the administration.
Trump had fired Rex Tillerson as secretary of state in mid-March and nominated Pompeo to replace him as the US' top diplomat shortly after the White House announced the President had agreed to meet with Kim.
Pompeo will need approval from the US Senate before he takes the role, but opposition has been growing on the committee voting to confirm him.
On Tuesday, Senator Jeanne Shaheen, member of the Senate Foreign Relations Committee, said she had "deep concerns" about Pompeo's nomination.
US Republicans have made it clear they will bring Pompeo's nomination to a vote in the senate regardless of the committee's findings, which would be unprecedented in body's history.