MAINE, Maine — Republican Sen. Susan Collins of Maine is criticizing President Donald Trump's decision to pull back U.S. troops from northern Syria.

Collins said Monday that the president made a "terribly unwise" decision to abandon Kurdish allies who were "our major partner in the fight against the Islamic State."

Trump on Monday defended his decision to pull troops from northern Syria, clearing the way for an expected Turkish assault.

Syria's Kurds accused the U.S. of turning its back on allies and risking gains made in the fight against IS.

Collins also took Trump to task over the weekend for asking China to investigate Democrat Joe Biden and his son. She told reporters in Maine that it's "completely inappropriate" for a president to encourage a foreign state to investigate a political rival.

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