Trump: Mattis out as of Jan. 1; deputy to be acting chief

WASHINGTON -- President Donald Trump announced on Sunday he would replace Defense Secretary James Mattis at the start of the new year, two months earlier than Mattis' planned departure.

"I am pleased to announce that our very talented Deputy Secretary of Defense, Patrick Shanahan, will assume the title of Acting Secretary of Defense starting January 1, 2019. Patrick has a long list of accomplishments while serving as Deputy, + previously Boeing. He will be great!" Trump tweeted.

Mattis announced his resignation on Thursday with a letter saying his views were not aligned with Trump, who said Mattis would retire at the end of February.

A source familiar with the matter said Trump was mad at the extensive coverage given to Mattis' resignation and therefore was forcing him to leave earlier than he originally planned.

Pentagon spokesman Col. Rob Manning said in a statement that "the secretary of defense serves at the pleasure of the President. The department remains focused on national security."

Mattis' retirement announcement on Thursday led much of Washington, including key Republicans, to express alarm about the change in leadership at the Pentagon. The announcement itself followed Trump's decision to call for a full withdrawal of troops from Syria and consideration of a drawdown in Afghanistan.

Shanahan, Trump's choice to replace Mattis on an interim basis, was confirmed as Mattis' No. 2 in the Pentagon last year by an overwhelming margin that came after a confirmation process that included a clash with the late Arizona GOP Sen. John McCain.

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