Disgraced San Diego Mayor Bob Filner agreed to resign yesterday in exchange for the city’s help defending him against a slew of sexual-harassment claims made by 17 women.

The accusers — including a great-grandmother and a retired Navy admiral — said the former 10-term congressman groped and kissed them and made salacious comments.

Filner, 70, was regretful and defiant during a City Council meeting, calling his resignation “the toughest decision of my life,” and insisting he was innocent of sexual harassment and was the victim of a “lynch mob.”

The city will pay Filner’s legal fees in defense of a lawsuit filed by the mayor’s former communications director — plus pay for any settlement costs except for punitive damages, said San Diego City Attorney Jan Goldsmith.

The communications director claimed the mayor wanted her to work without panties.