U.S. President Donald Trump said Thursday that Defense Secretary Jim Mattis is to retire at the end of February.

In this file photo taken on October 23, 2018, US Secretary of Defense James Mattis (L) and US President Donald Trump wait for a meeting with military leaders in the Cabinet Room of the White House in Washington, DC. US Defense Secretary Jim Mattis will be retiring at the end of February, President Donald Trump said Thursday, December 20, 2018. [File Photo: VCG]

Mattis will "be retiring, with distinction," after having served the administration as the defense chief for the past two years, Trump tweeted.

"During Jim's tenure, tremendous progress has been made, especially with respect to the purchase of new fighting equipment," the president said.

He added that a new secretary of defense "will be named shortly."