US envoy to anti-IS coalition resigns

Brett McGurk, the US special envoy to the anti-Islamic State group coalition, has resigned, a State Department official said Saturday, capping a chaotic week that saw the departure of Defense Secretary Jim Mattis and Donald Trump's stunning decision to pull troops from Syria.

McGurk's resignation, effective December 31, comes on the heels of Mattis's decision to quit the Trump administration over key disagreements with the US president, notably the Syria withdrawal.

Just last week McGurk, a Barack Obama appointee whom Trump kept on, said "nobody is declaring a mission accomplished" in the battle against IS -- just days before the president blindsided politicians and allies with his announcement of victory against the jihadist movement.

Trump on Saturday said that the jihadist group "is largely defeated."

"When I became President, ISIS was going wild," the president tweeted. "Now ISIS is largely defeated and other local countries, including Turkey, should be able to easily take care of whatever remains. We're coming home!"

Trump later took aim at McGurk on Twitter, referring to him as a "grandstander" who was quitting just before his time was up.