A strike deadline set for 12:01 a.m. Sunday came and went without word about whether the Toronto Public Library and the union representing its workers were able to reach a deal.

At a Saturday afternoon media briefing, the president of CUPE Local 4948, Maureen O'Reilly, said her bargaining team was not happy with the latest offer on the table.

"I regret that I have to say that I'm not very optimistic about what has come back and I'm not optimistic about a settlement at this point in time," O'Reilly said.

She said the union was still "working very hard" to negotiate a settlement, but librarians may have no choice but to walk off the job.

"We cannot sustain the type of concessions that are being asked for and demanded here at our table," O'Reilly said.

CUPE Local 4948, the union representing 2,400 library workers, has accused the Toronto Public Library Board of making unrealistic promises to the city earlier this year when it agreed to budget cutbacks.

In January, Mayor Rob Ford's budget was passed with a 10 per cent funding cut to libraries. Ford initially wanted to slash the library budget by $7 million, but council later agreed to cut only $3.9 million.

On Friday, O'Reilly said the library board agreed to concessions that "take away the rights of part-timers to have a decent quality of life and full-time opportunities."

She said the library has cut 107 full-time jobs and only 22 per cent of part-time workers -- most of them women -- get benefits.

Librarians have been working without a contract since Jan. 1, as part of greater labour negotiations with other indoor workers in Toronto.