Hong Kong's No. 2 government official resigned on Thursday in what is widely seen as preparation for a bid for the southern Chinese city's top leadership job.
Chief Secretary Carrie Lam tendered her resignation to Chief Executive Leung Chun-ying, who in turn submitted it to Beijing, the Hong Kong government said in a statement. Lam will be on leave from Friday.
The labor and welfare secretary, Matthew Cheung Kin-chung, will become acting chief secretary.
Hong Kong leader Leung is deeply unpopular and announced last month that he won't seek another term, citing family reasons. His five-year term ends in June.
Another potential contender for his job, Finance Secretary John Tsang, quit last month.
Hong Kong leaders are chosen by a 1,200-member panel of mostly pro-Beijing tycoons and elites, which is scheduled to make its pick in March. So far, retired judge Woo Kwok-hing and lawmaker Regina Ip have publicly declared their intention to run for the job of leading the city of 7.2 million.