Republican Illinois Rep. John Shimkus withdrew his support for President Trump over the administration's decision to pull their troops from northern Syria.

The Trump administration announced the policy shift late Sunday night, which has already harmed the U.S.-backed Kurdish forces in northern Syria. Turkish President Recep Tayyip Erdoğan said on Wednesday that he planned to push back the Kurdish People's Protection Units, a group that proved to be a key U.S. partner in the fight against ISIS.

Shimkus, who is not running for reelection in 2020 after serving in the House for over 20 years, told KMOX's Mark Reardon that he told his staff "to take my name off the I support Donald Trump list," and he added that he is "saddened for the Kurdish people."

Shimkus, 61, is not the only Republican to be critical of the president's decision to withdraw troops from the region. Republican Sens. Lindsey Graham of South Carolina, Marco Rubio of Florida, and Mitt Romney of Utah were some of the many conservative lawmakers who urged the president to reconsider his decision.