Departure of Cook, first Black woman to sit on central bank’s board, would allow US president to put forward a replacementDonald Trump has said he is firing the Federal Reserve governor, Lisa Cook, over allegations she committed mortgage fraud, in an extraordinary move that marks the latest escalation in the US president’s attack on the central bank’s independence.Trump wrote to Cook on Monday, telling her that he was removing her from her position “effective immediately”, based on the allegation from one of his allies that she had obtained a mortgage on a second home she incorrectly described as her primary