The head of the BBC's governing body has resigned after being asked by Prime Minister Theresa May to reapply for her job ahead of a major overhaul, the public broadcaster confirmed on Wednesday.
Rona Fairhead was only confirmed in her post four months ago by former premier David Cameron, a decision that his successor has now reversed.
In a statement, Fairhead said she believed there should be a "clean break" as the BBC implements major changes as part of a new 11-year governing charter due to be agreed with the government this year.
She was appointed to the four-year chairmanship of the BBC Trust in October 2014, but the post will technically be abolished under the reforms as the trust is replaced by a new Unitary Board.
In May, Cameron asked Fairhead to stay on and complete her term as chair of the new board, which will be more involved in the day-to-day running of the broadcaster.
But the appointment drew criticism from parliament's culture committee, which said the politically sensitive job should have been opened up to public competition.
May has now decided to re-rerun the process, according to a statement from the BBC Trust, and Fairhead said she will not be applying.
"The prime minister strongly encouraged me to take part in the new appointment process, for what would be a new four year term as BBC Chairman," Fairhead said.
"However, after much thought I have come to the conclusion that I should not do so.
"It is my belief that it will be better to have a clean break and for the government to appoint someone new."
The negotiation over the new charter is a delicate process for the BBC, which is widely loved in Britain but also draws political fire over its output because of its dependence on an annual licence fee.
The annual charge of £145.50 ($210, 184 euros) on all British households who watch live television raises more than £3.7 billion per year.
Ministers are due to present a draft of the new BBC charter on Thursday, according to the Financial Times, based on proposals published in May.