The slow-moving traffic that frustrated many motorists across the Greater Toronto Area last week following a light snowfall is being blamed on a breach of contract.

Last Wednesday, approximately five centimetres of snow coated Toronto as temperatures dropped to a low of - 5 C. Despite the relatively mild winter weather, however, traffic on many highways and roads came to a halt.

On the Queen Elizabeth Way, the surface was so icy at one point that Ontario Provincial Police officers were calling for salt trucks on their radios. But none came.

CTV Toronto's Paul Bliss says many motorists were also forced to navigate the slippery highway, between Burlington and Hamilton, without the help of road salt or sand.

According to Ontario's Transportation Minister Steven Del Duca, the dangerous driving conditions were a breach of contract.

"The contractor deployed their equipment about an hour later than they were contractually required to do," Del Duca told CTV Toronto on Tuesday.

He adds that the contractor may not have had enough road salt to de-ice the highways last week.

The Highway Maintenance Guidelines require that salting begins within 30 minutes of the start of a storm, and plowing to begin when two centimetres of snow has fallen. It also requires that the pavement is bare on major highways within eight hours of the start of a storm.

Del Duca says the province has not yet completed its investigation into why the snow and ice was not cleared on time last week. He says officials from the ministry are expected to issue a notice of non-compliance to the contractor in the coming days, and they could face stiff fines.

Ontario's highway maintenance standard says the failure to begin salting or plowing on time will result in a $5,000 per vehicle penalty for the contractor.

The Ministry of Transportation employs a number of different contractors to clear the highways during the winter. The MTO site lists all of the maintenance companies for each region.

For the Niagara, Hamilton, Toronto and York areas, Integrated Maintenance and Operations Services are responsible for clearing the roadways. And in Peel and Halton, TWD Roads Management Inc. is responsible for maintaining safe driving conditions.

With a report from CTV Toronto's Paul Bliss