Departing U.S. Secretary of State Rex Tillerson pledged Tuesday to ensure an "orderly and smooth" transition of his duties to Mike Pompeo, the director of the Central Intelligence Agency who President Donald Trump has picked as his replacement.

"What is most important is to ensure an orderly and smooth transition during a time that the country continues to face significant policy and national security challenges," Tillerson told reporters as the administration prepares for what will be a first summit between the United States and North Korea by May.


Tillerson made the remark after Trump dismissed him and named Pompeo as his new chief diplomat earlier Tuesday due to rifts over a host of issues such as the Iran nuclear accord and the approach toward North Korea.

"When you look at the Iran deal, I think it's terrible. I guess he thought it was OK. I wanted to either break it or do something, and he felt a little bit differently," Trump said, in reference to Tillerson. "So we were not really thinking the same."

Pompeo, considered a hawk on Iran, opposes the nuclear deal with the Islamic republic. Citing his suggestion last year that the administration may be contemplating the goal of regime change in North Korea, some foreign policy experts said Washington may take a tougher posture toward Pyongyang.

Analysts believe Pompeo's appointment will produce a more consistent public message on foreign policy for an administration that has spoken in multiple voices on issues such as North Korea's development of nuclear weapons and ballistic missiles.

Pompeo is expected to be sworn in as the secretary of state after undergoing a Senate confirmation hearing scheduled for April.

"As I shared with the president, the committee will consider his nomination as expeditiously as possible," Bob Corker, chairman of the Senate Foreign Relations Committee, said in a statement.

Tillerson said he will delegate all of his responsibilities to Deputy Secretary of State John Sullivan at the end of Tuesday, and that he will formally leave office on March 31.

"Between now and then, I will address a few administrative matters related to my departure and work toward a smooth and orderly transition for Secretary of State-designate Mike Pompeo," he said.

A former officer in the U.S. Army, Pompeo served as a Republican congressman from Kansas before taking the helm of the CIA.

He impressed Trump during daily intelligence briefings and became a trusted policy adviser, even on issues beyond the spy agency's normal mandate such as health care, according to U.S. media.

"(Trump's) leadership has made America safer and I look forward to representing him and the American people to the rest of the world to further America's prosperity," Pompeo said in a statement.

CIA Deputy Director Gina Haspel is in line to succeed Pompeo, making her the first woman to be chosen for the role, according to the White House.

Tillerson's departure has been anticipated for some time. He was reported last fall to have privately called Trump a "moron" and considered stepping down.

Tillerson, a former chief executive of Exxon Mobil Corp. who took office Feb. 1, 2017, has also expressed more openness to dialogue with North Korea than Trump.

The reshuffle came soon after Tillerson returned from an African trip and with no face-to-face talks with Trump.

It also came after Trump last week accepted North Korean leader Kim Jong Un's offer for talks on the denuclearization of the Korean Peninsula in what will be the first summit between the two countries in the absence of diplomatic ties.

The rift between Trump and his chief diplomat over their approaches to North Korea became evident in December when the White House dismissed Tillerson's offer for unconditional talks with the isolated nation.