The drivers' union issued a letter to parents Tuesday saying drivers wouldn't strike during the holiday season, but didn't rule it out for after the holidays.
Department of Education spokeswoman Natalie Ravitz criticized the union for continuing to threaten what she says is an illegal strike. She says the mayor had to prepare for the possibility of a stoppage.
The city informed the union last month it would seek bids for a new school bus contract for special education pre-kindergarten and pre-school students.
At the time, Bloomberg said union representatives told the city they would institute a systemwide strike unless it committed to job protections for current drivers.
On Tuesday, drivers, mechanics and escorts rallied at City Hall.
They're pushing the city to guarantee them job protection.
The problem is that the drivers don't work for the city. They work for private yellow bus companies that compete for city contracts.
Mayor Michael Bloomberg says that means the city cannot guarantee their jobs, even if it wanted to.