Glynn Jones, the top official at Brighton and Hove Council, is to retire later this year.

He will go at the end of October, giving the authority eight months in which to fill the £90,000-plus post of chief executive.

He said today: "This is not a sudden decision but one of long-term planning.

"The council is about to embark on a cycle of major change, both in political structure and in the way we work with partners in the city.

"These changes will take some years to complete and I believe a new chief executive should have the opportunity to steer the city council through the changes from start to end."

Mr Jones, 55, was appointed to head the former Brighton Council in 1989. He is one of the longest-serving chief executives in the country.

Before coming to Brighton, he worked as borough secretary in the London borough of Haringey.

He has seen the council through a period of unprecedented change.

He helped arrange the complicated merger with Hove in 1997, which involved taking over services such as education from East Sussex County Council.

Last year he helped the council campaign for city status, which was granted in December.

He has also helped the council become a pioneer, abandoning the old committee system in favour of a new-style leader and cabinet model.

This year the council may hold a referendum on whether it should have an elected mayor.