Filner is expected to make the announcement immediately after the council votes in a closed session, which is scheduled for 1 p.m. Friday, KGTV in San Diego reports.
Filner was spotted leaving City Hall with several boxes Wednesday night.
San Diego's city attorney, city leaders and the mayor's attorneys announced earlier Wednesday that a proposed resolution was reached following three days of mediation.
The mayor's former communication's director, Irene McCormack Jackson, was the first to go public and is the only one to file a lawsuit against Filner and the city.
McCormack and her attorney, Gloria Allred, both attended the first day of mediation. At a news conference Thursday, Allred said she did not know details of the proposed resolution.
"We do not know the details of the so-called deal, and therefore we did not approve any so-called deal," said Allred.
Allred was joined by Filner's former fiance, Bronwyn Ingram. Ingram spoke out on camera for the first time since calling off her wedding to Filner. She broke up with him as sexual harassment allegations against him came to light. Ingram said she wants the mayor to resign.
"I'm hopeful that tomorrow will begin a healing process and that attention will return to the needs and concerns of the people of San Diego," said Ingram.
Allred and Ingram both want council members to vote down any deal that leaves the city liable for Filner's alleged inappropriate behavior.
"There should be no payoff for Mayor Filner. It would be a slap in the face to the mayor's many victims to see him get anything from the city of San Diego," said Allred.
Eyewitness News asked Allred if she will withdraw her lawsuit if the council votes to fund Filner's defense. Allred says unless the lawsuit itself is settled, she will continue fighting.
Meantime, another woman has come forward to accuse Filner of alleged sexual misconduct. This time, the allegation includes a photo and witnesses. San Diego business owner Dianne York says she went to Filner's office with three staff members for a business meeting. It was her first time meeting him.
"When we got up to say our goodbyes, I asked for a photo from the mayor because I thought it was exciting to get to meet the mayor for the first time," said York.
During a news conference on Wednesday, York said Filner inappropriately touched her when she posed with him for the photo.
"There was a hand that went to my back, to my buttocks, and I was shocked. It was inappropriate, and I was startled at the time," said York.
York says she has reported the incident to the San Diego County Sheriff's Department. She is the 18th woman to openly accuse Filner of making unwanted sexual advances.
If the mayor announces his resignation, then City Council President Todd Gloria becomes acting mayor. A special election for a replacement will then take place 60 to 90 days later.