Labor leaders for Bay Area Rapid Transit workers say they are not giving 72-hour notice for a second strike.
Antonette Bryant, president of the Amalgamated Transit Union Local 1555, and members of the Service Employees International Union Local 1021 said Monday they are not giving notice because they want to leave every possible option for resolution open.
If no deal is reached, the unions could strike again by Friday when a 60-day cooling-off period expires.
BART spokesman Jim Allison says officials are working hard trying to reach a settlement.
BART officials have said they are about $89 million apart from a four-year contract with the unions, while the unions say the gap is about $30 million over three years.
BART workers walked off the job for four-and-a-half days in July.