PROVIDENCE, R.I. (WPRI) – The city’s school busing provider says it offered its bus drivers wage increases averaging 5% a year for four years, but the local Teamsters union voted against the proposed deal.

Now the two sides are at an impasse, with the union threatening to strike if First Student Inc. does not agree to pay drivers a minimum of three hours in the morning and three hours in the afternoon, according to Nick Williams, an assistant business agent with Teamsters Local 251.

The union originally said it planned to begin striking Feb. 23, but First Student invoked a 21-day “cooling off” period to help resolve the dispute. The three-week period where neither side will take action is part of the company’s national master agreement with the union.

“First Student remains in communication with the Teamsters’ National Union Committee and is hopeful for a timely resolution,” the company said in a statement.

The company said it offered to pay workers for a minimum of 2.75 hours per shift in addition to the proposed wage increases. She said drivers earn between $17.75 and $24 per hour.

No school bus drivers in the state are paid for three-hour shifts, according to Williams, the union representative.

First Student Inc. is the largest school bus provider in North America, operating in 38 states and eight Canadian provinces. The company’s agreement with the city expires at the end of the school year and the city recently went out to bid for new busing providers. The city is not responsible for negotiations with bus drivers.

This wouldn’t be the first time bus drivers went on strike in Providence.

In 1987, drivers walked off the job after accusing then-busing provider Ryder Student Transportation Service, of failing to to keep buses in “safer operating condition,” according to a Providence Journal report from the time. The busing company said the workers went on strike because it refused to provide wage increases. Police officers armed with lollipops drove some students to school.

First Student, a division of the British company FirstGroup Plc, purchased Ryder Student Transportation in 1999.

In 2000, the drivers went on strike for nearly a month after the union was unable to come to terms on a new contract with First Student. The union won a pay increase and health insurance for eligible drivers.Dan McGowan ( dmcgowan@wpri.com ) covers politics, education and the city of Providence for WPRI.com. Follow him on Facebook and Twitter: @danmcgowan