"I hope the press will respect the anonymity of the women and witnesses involved to protect the integrity of the process," Ms Sullivan said in a brief statement.

The investigation into allegations of sexual harassment by Cr Robert Doyle will start on Tuesday, when Dr Ian Freckelton??? QC begins interviewing councillors and staff.

Cr Doyle will take leave for a month while the investigation is under way, and his deputy, Cr Arron Wood, will be acting lord mayor.

Dr Freckelton began practising as a barrister in Melbourne in 1988, and has been a Senior/Queen's Counsel since 2007. He was appointed a Judge of the Supreme Court of Nauru in October this year. He is also a lawyer member of the Mental Health Tribunal of Victoria.

Premier Daniel Andrews, asked by reporters about the allegations on Monday, said they were "very serious claims" and needed to be thoroughly investigated. He said he would await the findings of the council's investigation before commenting further.

On Friday, Ms Sullivan, a member of the "Team Doyle" election ticket, resigned from Melbourne City Council, after lodging a sexual harassment complaint with chief executive Ben Rimmer.

She alleged Cr Doyle sexually harassed and indecently assaulted her, including grasping her breast and making explicit comments.

Cr Doyle said on Sunday that he was shocked by the allegations, and would take a month's leave. He said this "must not be interpreted as an admission or concession".

"I welcome the investigation and will co-operate fully to clear my name," he said in a statement posted on Twitter.

Melbourne City councillors will hold a special meeting on Tuesday, where they will see each other for the first time since Sunday's explosive allegations against the lord mayor became widely known.

One councillor described it as a "solidarity meeting".

Another said there had been a strict warning from management at the city council not to talk to the media about anything involving the case. "They have said to us that because of the process [involving Mr Freckelton] we are to not say anything," they said.

Local Government Minister Marlene Kairouz has been notified of the countback of votes to determine who replaces Ms Sullivan on the council. The Victorian Electoral Commission will do the count. "The timing for the countback of votes is yet to be finalised, but is not expected to take place before 12 January," a Melbourne City Council spokesman said.

Cr Jackie Watts on Monday spoke out about the allegations, saying these were "sad days" for Melbourne City Council.

She said councillors had been shocked by the claims levelled against Cr Doyle.

"We are all shocked and of course Tessa is feeling it greatly," she told radio station 3AW. "I think it would be a very difficult time for her. It takes a very brave woman to speak up in this way."

Cr Watts said the allegations put everybody in a "very difficult position".

Cr Watts, who said her council portfolio includes gender equity, took the Lord Mayor before a councillor conduct panel in her first term in local government, over allegations of bullying.

The allegations against Cr Doyle were dismissed after the inquiry found the complaints could not be proved.

Asked about her relationship with Cr Doyle now, Cr Watts told 3AW it was professional and "cordial".

Cr Doyle has stood aside from his position as chairman of Melbourne Health, which runs Royal Melbourne Hospital, with the group posting a statement on Twitter on Sunday saying he would take one month's leave.

Cr Doyle is also an associate with management consultants Nous Group. The company said his role there was independent of his position of the lord mayor of Melbourne.

"Robert has taken leave from his role with Nous Group while the City of Melbourne undertakes a thorough investigation to determine the veracity of the allegations against him," a spokeswoman for Nous Group said in a statement.

It came as a national association representing women in councils on Monday called for uniform procedures when dealing with complaints like those made at Town Hall.

"For women councillors, the council and chamber are their workplace - they have the right to feel safe at work and supported if they make a complaint," said Boroondara councillor Coral Ross, also president of the Australian Local Government Women's Association.

She said there were different procedures at Australian councils when a complaint was made.

"In some states, a councillor has to make a complaint to the mayor and that can be difficult if the complaint is about the mayor," said Cr Ross. "Councils are political places, so there needs to be an independent process outside the political arena to give confidence to all involved."

With Robyn Grace

mperkins@theage.com.au

clucas@theage.com.au