HM Revenue & Customs (HMRC) chief executive and permanent secretary Dame Lesley Strathie is stepping down from her role because of ill health.
Strathie, who was diagnosed with cancer in July, was due to return to work this autumn but has now decided to leave the post.
"Over the last 40 years, Lesley has devoted her life to public service," said head of the home civil service Sir Gus O'Donnell. "She has been a wonderful role model for all civil servants, working her way from the bottom to the very top of the Civil Service,"
HMRC said arrangements for appointing a successor will be announced shortly.
Strathie joined HMRC in November 2008 from Jobcentre Plus where she was chief executive.
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