Outgoing U.S. Defence Secretary James Mattis urged his employees to avoid distraction in a farewell memo Monday, adding that the department “remains in the best possible hands.”
“Let nothing which is transpiring, change, hinder or delay your military movements or plans,” he wrote, quoting a Civil War-era letter from President Abraham Lincoln to Gen. Ulysses S. Grant on Feb. 1, 1865.
Mattis hinted at trying times in his brief message, echoing the veiled criticism included in his resignation letter to U.S. President Donald Trump earlier this month. He did not mention the president by name in his farewell memo.
WATCH BELOW: Mattis resigns after clashing with Trump on troop movements
“I am confident that each of you remains undistracted from our sworn mission to support and defend the Constitution while protecting our way of life,” Mattis wrote to his employees on Monday, adding:
“Our Department is proven to be at its best when the times are most difficult.”
He also encouraged employees to “keep the faith in our country and hold fast, alongside our allies, aligned against our foes.”
Mattis handed in his resignation on Dec. 21 after Trump issued a surprise order to withdraw troops from Syria and scale back military involvement in Afghanistan.
WATCH BELOW: Mattis follows through on order to withdraw troops from Syria as one of his final acts
Mattis was initially slated to depart in February, but Trump moved up his departure the day after it was announced. Trump reportedly axed Mattis early because he was unhappy with news coverage of Mattis’ resignation letter, according to a Reuters report.
Mattis issued a rebuke to Trump’s foreign policy in his resignation letter, suggesting that the president was damaging important alliances while failing to recognize the threats presented by hostile rival nations.
“My views on treating allies with respect and being clear-eyed about both malign actors and strategic competitors are strongly held and informed by over four decades of immersion in these issues,” Mattis wrote in the letter.
“Because you have the right to have a Secretary of Defense whose views are better aligned with yours on these and other subjects, I believe it is right for me to step down from my position.”
Deputy Secretary of Defence Patrick Shanahan, a former Boeing executive with no military experience, will take over for Mattis on Jan. 1.