Canada has enlisted the army to assist in firefighting and recovery efforts in Alberta, after wildfires forced thousands to evacuate their homes and prompted several oil and gas producers to halt operations in the country's main crude oil producing province.

Canadian Prime Minister Justin Trudeau said on Thursday that the armed forces were deployed following Ottawa's approval of Alberta's request for federal support, after more than 100 wildfires broke out across the province in western Canada last week.

Trudeau wrote on "Twitter" that the army "will provide support in firefighting and air transport resources, help evacuate isolated communities, and ensure the safety of people."

The widespread fires marked a strong start to the wildfire season in Alberta, putting the disaster management skills of Alberta Premier Danielle Smith, along with her party's policies, under scrutiny ahead of the provincial election scheduled for May 29.

A drop in temperatures over two days gave firefighters a respite and allowed some oil and gas companies to resume halted production on Wednesday, but forecasts indicate a rise in temperatures early next week.