Bob Filner has vacated his city hall office and reportedly agreed to resign as mayor of San Diego as part of a mediation deal in a sexual harassment lawsuit.

The mayor's exit is expected to be confirmed by the city council on Friday following days of mediation talks and weeks of allegations from at least 17 women who accused Filner of making unwanted sexual advances.

He agreed to quit, bid farewell to staff and loaded boxes into an SUV outside city hall on Wednesday night, several media outlets reported. But the lawyer for one of Filner's accusers said on Thursday the deal does not resolve her lawsuit, potentially creating an impasse ahead of the city council vote.

Filner's departure would pre-empt a recall effort and end a political saga which destroyed the outspoken Democrat's support and made headlines across the US.

The city's attorney, Jan Goldsmith, announced a deal on Wednesday after three days of talks between Filner, his three attorneys, Goldsmith and two council members. A former federal judge, J Lawrence Irving, mediated.

Goldsmith told reporters details of the agreement would not be revealed publicly until the council debated it in a closed session on Friday. All nine members have said Filner, 70, must go. The Democratic national committee had scheduled a vote demanding Filner quit for this Friday.

Isolated and besieged, there was little doubt the former congressman would go. The issue was whether the city would help pay his legal fees and potential damages in the sexual harassment lawsuit filed by his former director of communications, Irene McCormack Jackson.

She was the first to go public last month, alleging Filner asked her to work without underwear, demanded kisses and whispered in her ear while dragging her in a headlock.

"He is not fit to be the mayor of our great city," McCormack said. "He is not fit to hold any public office."

At least 16 other women swiftly followed, including city officials, a university dean and army and navy veterans. Allegations ranged from inappropriate language to groping, manhandling and bullying.

McCormack's attorney, Gloria Allred, held a press conference in Los Angeles on Thursday during which she said the deal doesn't resolve her lawsuit. Allred said she never signed off on a settlement and doesn't know any details. She wants Filner to resign but doesn't believe he should have legal bills covered by the city and urged the council to reject the proposal if it includes that provision.

"There should be no payoff for Mayor Filner," she said.

The latest allegation came earlier this week from Dianne York, who said Filner placed his hand on her bum while she posed for a photo with him after a meeting at his office about three months ago. She said she reported it to the San Diego County sheriff's department.

As the accusations mounted Filner admitted disrespecting and at times intimidating women and took two weeks off for therapy. "Words alone are not enough," he said. "I must take responsibility for my conduct by taking action so that such conduct does not ever happen again."

It was too little, too late, however, to stem a grassroots revolt.

Elected last November to a four-year term, the city's first Democratic mayor in two decades had made enemies, and energised supporters, with a combative, bruising style.

Should Filner resign, city council president Todd Gloria will become acting mayor until a special election is held. Filner would become the fourth of San Diego's past seven mayors to resign – all for different reasons.