The much-anticipated investigation and report into sexual harrassment allegations against Melbourne Lord Mayor Robert Doyle has been delayed amid reports he is “suffering serious ill health”.

City of Melbourne Chief Executive Officer Ben Rimmer said the “investigative process” had been “extremely stressful for all parties”.

“We recognise that the investigative process has been extremely stressful for all parties and their families, despite the best efforts of the City of Melbourne and the independent investigation,” Mr Rimmer said in a statement on Friday.

“We support the Lord Mayor’s focus on his health and we are very hopeful that he makes a full and speedy recovery. We are very conscious of the need to support all Councillors and employees during this difficult time,” the statement read.

Mr Doyle’s illness was understood to be stress-related and this was expected to slow the finalisation of an investigation and report into the allegations, the City of Melbourne said.

Mr Doyle stepped aside as mayor in December when fellow councillor Tessa Sullivan resigned after claiming he sexually harassed her.

Mr Doyle has strongly denied the allegations but would not return to work until the investigation is complete.

Top lawyer Ian Freckleton QC was hired to investigate the allegations and his interim report had been imminent, however, no timeline had been specified for delivery of the final report.

Mr Rimmer said it was now likely that the investigation would report in two stages, interim and final.

“We are very much aware it is in the interests of everyone involved that the investigative and reporting processes are thorough and completed as quickly as possible,” he said.

A second woman in January accused Mr Doyle of touching her leg under a table and allegedly making offensive remarks at a Melbourne Health awards ceremony in June 2016.

This led Health Minister Jill Hennessy to order a separate probe and Mr Doyle took leave of his role as Melbourne Health chairman.

Melbourne councillors were due to discuss the Freckleton investigation at a committee meeting on Tuesday.

Mr Rimmer took aim at the media for “inflammatory, damaging or speculative information or commentary” over the allegations.

“This process will take as long as it needs to, consistent with the overarching principles of natural justice and procedural fairness for complainants and the lord mayor,” he said.

— with AAP