KITCHENER -- The Region of Waterloo is shedding some light on the terms that it offered to Grand River Transit union members.

In a statement released early Tuesday, the region says it offered a "comprehensive settlement" that includes a six per cent wage increase over the course of three years for bus operators, dispatchers and service attendants.

The settlement also included a 15 per cent pay increase over three years for mechanics, the statement reads.

Another statement from the region says that the region and Unifor had already agreed to spending about $1.7 million on safety barriers for all 278 of the GRT's buses over the next three years.

"I am extremely disappointed the Union membership did not ratify the tentative collective agreement that was recommended by their bargaining team," said Mike Murray, Chief Administrative Officer.

"We have worked hard over the last three months and especially over the last two weeks to identify and address concerns raised by the Union, including those related to safety."

In a statement, the region says it hopes to negotiate a fair economic and safety package for GRT workers.

"Local 4304, which represents drivers, mechanics, vehicle service attendants and dispatchers at GRT, will work quickly to set up bargaining dates with the employer to work through the remaining issues," the union says in a post on its Facebook page.

It also said it would not be sharing any details of the tentative agreement that was voted down on Sunday.

Bus drivers were among about 700 GRT employees who went on strike on Tuesday at 5 a.m.