TORONTO - Transportation Minister Donna Cansfield says big rigs will soon be travelling slower along Ontario highways.

Cansfield says the Ontario government is making it mandatory for large commercial vehicles to use speed limiters.

She says speed limiters would cap the speed of transport trucks and other large vehicles at 105 km/h.

Cansfield says the reason for capping the speed five kilometres above most speed limits is to give truckers the opportunity to pass slower vehicles.

The government says speed limiters will help improve safety on the road and cut greenhouse gas emissions in the province.

Cansfield says the Ontario Trucking Association played a large role in pressuring the government to enforce mandatory speed limiters on Ontario highways.