Chair of the BBC Trust Rona Fairhead is to step down, the organisation has confirmed.
Her resignation comes after Theresa May indicated she would have to apply again for the job she was reappointed to by David Cameron just four months ago.
In a statement Ms Fairhead said she decided to quit rather than take part in the reapplication process for the role.
She said: “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.
“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, and for me to continue my career in the private sector as I had always planned to do after my existing term ended in 2018.”