Aviva UK insurance boss Andy Briggs has stepped down as part of a reshuffle being led by new chief executive Maurice Tulloch.
Tulloch said he will lead a review of the UK insurance group's businesses "to ensure the appropriate management structure".
Briggs had been tipped as a possible replacement for former CEO Mark Wilson, who had been on leave since October, until Falkirk- born Tulloch was appointed last month.
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He will remain with the group, which has a major presence in Perth and Bishopbriggs, until October 23 to help support an "orderly transition" but has been replaced as CEO of UK insurance on an interim basis by Angela Darlington, currently Aviva's group chief risk officer. She has been with Aviva since 2001.
Briggs, whose salary and remuneration package is worth £854,000, was previously head of Scottish Widows and worked with Lloyds Banking Group.
He joined the Aviva board in April 2015 to lead its enlarged UK Life business following the acquisition of Friends Life where he was group chief executive.
He was also chair of the Association of British Insurers and the Government Business Champion for Older Workers.
Colm Holmes, CEO of Aviva Canada and Global Corporate & Speciality, and Patrick Dixneuf, who becomes CEO of Aviva's European businesses and remains as CEO of Aviva France, will join Aviva's Leadership Team.
Aviva will not seek to appoint a new CEO International (the role filled by Tulloch before he became group CEO).
Tulloch said: "These appointments are an important first step to bring greater energy, pace and commercial thinking to Aviva. Andy Briggs will be missed. Andy is a brilliant leader and a good friend.
"Aviva has benefited enormously from his extensive industry experience and his integrity and we wish him well for the future. I look forward to working with him during the transitionary period."
Sir Adrian Montague, chairman of Aviva, said: "Andy has made a great contribution to Aviva's business since he joined the Group following the acquisition of Friends Life in 2015.
"On behalf of the board, I would like to pay particular tribute to Andy for his conduct throughout the process to select a new CEO and afterwards, and Andy will leave with our best wishes for his future career."
