President Donald Trump has taken to Twitter to announce the appointment of his new chief of staff, Mick Mulvaney. In a tweet on Friday evening, Mr Trump announced Mr Mulvaney would take on the position in the capacity of caretaker as acting chief of staff, saying he had done and “outstanding” job in his current position within the administration. Former Congressman Mr Mulvaney, 51, is presently the director of the Office of Management and Budget, but will take over from General John Kelly as chief of staff in the new year. After persistent swirling rumours around Kelly’s potential departure, Mr Trump finally confirmed it last week. In his tweet announcing Mr Mulvaney’s appointment he said Mr Kelly had “served our country with distinction”, calling him “a great patriot”. Mr Mulvaney was not the first to be asked to take up to role on a temporary basis. Mr Trump’s first choice, Vice President Mike Pence’s chief of staff Nick Ayers, turned down the job after Trump announced Mr Kelly’s departure. Next, speculation was rife that former New Jersey governor Chris Christie was the frontrunner. Mr Christie withdrew from consideration Friday afternoon. Mr Trump met Mr Christie in the White House residence on Thursday after a holiday reception. But people close to the president on Friday said Mr Christie damaged his standing with Mr Trump because of a memoir he is publishing in January that is expected to be critical of the president and the family of his son-in-law, Jared Kushner. Following Mr Trump's announcement, Mr <span>Mulvaney</span> thanked the president for the "tremendous honour" of appointing him, writing "I look forward to working with the president and the entire team". Mr Trump and Mr Mulvaney met at the White House on Friday and then spoke again on the telephone in the late afternoon, an official who spoke on the condition of anonymity said. Mr Mulvaney’s current deputy, Russell Vought, will take over management of the budget office, the official added.