Updated

President Trump on Saturday night reacted to the resignation of Brett McGurk, the U.S. envoy for the global coalition to defeat the Islamic State group (ISIS), while also offering a new response to the departure of his defense secretary, James Mattis.

Trump took to social media to say he'd neither met nor appointed McGurk, while also suggesting that the official was a “grandstander.”

“Brett McGurk, who I do not know, was appointed by President Obama in 2015. Was supposed to leave in February but he just resigned prior to leaving. Grandstander?” Trump tweeted. “The Fake News is making such a big deal about this nothing event!”

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McGurk tendered his resignation following Trump’s decision to pull U.S. troops out of Syria, Fox News confirmed earlier Saturday.

U.S. officials said this week that the Trump administration was making plans to pull all 2,000 troops out of Syria.

In his resignation letter to Secretary of State Mike Pompeo, McGurk said that ISIS was on the run but wasn’t yet defeated and that U.S. military’s work in Syria had not yet been completed, the Associated Press reported.

“If anybody but your favorite President, Donald J. Trump, announced that, after decimating ISIS in Syria, we were going to bring our troops back home (happy & healthy), that person would be the most popular hero in America,” Trump continued on Twitter Saturday. “With me, hit hard instead by the Fake News Media. Crazy!”

BRETT MCGURK, US ENVOY TO ANTI-ISIS COALITION, RESIGNS IN WAKE OF TRUMP DECISION TO PULL TROOPS FROM SYRIA

Fox News confirmed that McGurk submitted his resignation letter on Friday, just one day after Mattis.

Trump revealed Thursday that Mattis would “be retiring, with distinction, at the end of February” as head of the Defense Department. The president went on to praise the “tremendous progress” made during Mattis’ time in the role, adding that he’d been “a great help to me in getting allies and other countries to pay their share of military obligations.”

However, on Saturday, Trump took a somewhat different tack, saying he'd given Mattis “a second chance” when offering him the position of defense secretary.

“When President Obama ingloriously fired Jim Mattis, I gave him a second chance,” Trump tweeted. “Some thought I shouldn’t, I thought I should. Interesting relationship-but I also gave all of the resources that he never really had. Allies are very important-but not when they take advantage of U.S.”

Trump may have been referring to a 2013 report by Foreign Policy that said Mattis wasn't informed of his ouster by the Obama administration as head of U.S. Central Command until an aide passed him a note saying the Pentagon had named his replacement. Mattis had succeeded David Petreaus in the role.

DEFENSE SECRETARY JAMES MATTIS TO RETIRE AT THE END OF FEBRUARY, TRUMP SAYS

In Mattis’ resignation letter to Trump, the former Marine Corps general acknowledged that a strong nation relies on a "comprehensive" network of alliances, and must be "resolute and unambiguous" in approaching countries with strategic differences, citing China and Russia.

"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," Mattis wrote.

Sources told Fox News this week that Mattis' resignation was "in protest" against the president's national security policies.

Fox News’ Adam Shaw, Gregg Re and The Associated Press contributed to this report.