The behaviour of some Whittlesea councillors has been blamed for chief executive Simon Overland’s shock decision to take indefinite leave from the troubled council.

Mr Overland, who was appointed to the council’s top job in 2017 for a period of five years, issued a statement on Wednesday stating that he held concerns for his health and safety.

He said the past two years at the council had been “very difficult” as a result of the behaviour of some councillors.

The statement said interactions between councillors, and some councillors and staff, was not in keeping with contemporary workplace health and safety requirements.

“Despite many attempts over the past two years, I have been unsuccessful in achieving improvement here, and in many respects the behaviours of some councillors have deteriorated, therefore increasing the risks to health and wellbeing,” Mr Overland said.

“The situation has been very difficult now for two years, but with recent changes on council, I now regrettably find my own health and safety significantly affected and accordingly, as of now, I am taking related leave.”

Mr Overland said he was unsure when he would return to the council. The council will be led by the executive leadership team during his absence.

Mr Overland, who is due to give evidence at a Royal Commission into Victoria Police’s use of a criminal barrister, known as Lawyer X, as an informer, has faced criticism from some councillors over the past year.

In December 2018, five councillors failed to attend a council meeting after raising concerns about Mr Overland remaining as chief executive while the Royal Commission took place.

At the time, Cr Norm Kelly called for Mr Overland to step down without pay until the Royal Commission concluded.

Mr Overland was an assistant and deputy commissioner at the time Lawyer X provided police with information.

In April, then deputy mayor Tom Joseph warned Mr Overland was in danger of losing the council’s confidence.

Cr Joseph said Mr Overland had denied councillors information required to do their jobs, saying the information was operational.

Cr Joseph has since declared his full confidence in Mr Overland.