Pompeo to meet with top North Korean official

Senior Trump administration officials are also coordinating directly with North Korean counterparts at the Korean demilitarized zone and in Singapore, Sanders said.

US officials are racing to lay the groundwork for President Donald Trump to meet with North Korean leader Kim Jong Un in Singapore next month, less than a week after Trump pulled out of the planned summit.

The President also plans to consult with Japanese Prime Minister Shinzo Abe at the White House on June 7, Sanders said.

"Since the President's May 24th letter to North Korean leader Kim Jong Un, the North Koreans have been engaging. The United States continues to actively prepare for President Trump's expected summit with leader Kim in Singapore," Sanders said.

Sanders' statement followed a series of tweets from the President in recent days indicating that the planned summit with North Korea is back on track, with US officials aiming to hold the summit on the previously scheduled date of June 12.

CNN reported earlier Tuesday that Chol, the vice chairman of the Central Committee, was traveling to the US for talks on North Korea -- making him the most senior North Korean official to visit the United States since 2000.

Pompeo's meeting with Chol and the series of discussions this week between US and North Korean officials are the most substantive indication yet that the summit is still in the works despite Trump's letter to Kim Jong Un last Thursday canceling the summit.

Trump canceled the summit with Kim after the North Koreans threatened a "nuclear showdown" and slammed Vice President Mike Pompeo as a "political dummy."

The tensions have once again cooled in the wake of Trump's letter and Trump has made clear he is eager for the summit to take place on June 12 -- but US officials have warned publicly and privately that they would be strained to reschedule the summit for that date.

"June 12 is in 10 minutes," a senior White House official said Thursday from the White House podium after Trump issued his letter, explaining that US officials had already lost a week during which North Korean officials went radio silent.

Now, several top US officials including US Ambassador to the Philippines Sung Kim -- a former negotiator with North Korea -- National Security Council director for Korea Allison Hooker and Assistant Secretary of Defense for Asian and Pacific Security Affairs Randy Schriver are meeting with North Korean counterparts at the DMZ this week.

Joe Hagin, the deputy White House chief of staff for operations, has arrived in Singapore for logistics meetings, Sanders said on Tuesday.

Sanders also said John Bolton, the national security adviser, 'has had calls with his South Korean and Japanese counterparts virtually every day."