Dr Diamond will take on the role of chief executive at Monash City Council. She informed Yarra City councillors of her decision after a council meeting last night.Mayor Geoff Barbour notified staff of Dr Diamond’s decision by email this morning. Her last day will be April 6. Dr Diamond has worked at the council for four years, overseeing about 850 staff.

The council will advertise for a new chief executive soon.

In a written statement, Cr Barbour praised Dr Diamond, saying she had been ‘‘instrumental in many of Yarra’s major achievements’’ including the redevelopment of Victoria Park and Collingwood Leisure Centre.

‘‘We are very sorry to see her go, but realise we must now look to the future with a new CEO and a new chapter in Yarra’s history,’’ he said.

Socialist councillor Stephen Jolly said Dr Diamond’s decision came as a shock to all councillors. He wished her well, and said a new CEO presented an opportunity to fix what he and fellow socialist councillor Anthony Main claim is a ‘‘pro-development culture’’ in the planning department.

Cr Main said: ‘‘The pressure is now on them to ensure we get a CEO who can bring this department into line with community expectations. In an election year this is something people will judge them on come October.’’