NEW YORK (AP) — In an unprecedented move, U.S. President Donald Trump said that he’s firing Federal Reserve Governor Lisa Cook — marking a sharp escalation in his efforts to exert greater control on one of the most powerful financial institutions in the world.

Trump took to social media Monday night to announce that he would be removing Cook, effective immediately, over allegations that she committed mortgage fraud before she joined the board. In response, Cook said that she would not step down — and maintained that the president has no authority to fire her.

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