Republican lawmaker Marjorie Taylor Greene, a longtime ally of Donald Trump who recently had a dramatic falling out with the president, said on Friday she was resigning from the House of Representatives effective Jan. 5.

"Loyalty should be a two-way street" while Congress "has mostly been sidelined" under the Trump administration, Greene posted in a lengthy resignation statement on social media.

The dispute between Trump and the Georgia lawmaker has fueled concerns among some Republicans that Trump's "Make America Great Again" base could fracture a year before midterm elections, when Democrats hope to regain control of Congress.

Greene's resignation will narrow the Republican majority in the House to 218 members over the Democrats' 213. Republicans have a 53-47 majority in the Senate.

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