Firefighters battling a massive blaze in Canada's energy heartland are being aided by a second day of light rain and winds holding flames back from oil sands facilities.
The wildfire in northern Alberta has blackened more than 500,000ha, six times the size of New York City, since it erupted this month.
It has forced widespread evacuations, destroyed entire neighbourhoods in the Fort McMurray area and triggered a prolonged shutdown that has cut Canadian oil output by a million barrels a day.
The fire's footprint had already exceeded the total area burned during Alberta's entire 2015 fire season, and it jumped Thursday into the neighbouring province of Saskatchewan, although no evacuations have been ordered there so far.
The fire's growth slowed on Friday (Saturday AEST) as firefighters were helped by colder, damper weather that began a day earlier and vastly improved air quality, provincial authorities said.
"We expect to hold this fire in place over the weekend," Alberta Wildfire Manager Chad Morrison told a news conference.
Authorities plan to roughly double the number of firefighters over the next two weeks to about 2100 personnel backed by bulldozers and aircraft dumping flame retardant.
The weather, which included winds pushing flames away from key oil sands assets, offered a glimmer of hope for crude operations, Statoil saying on Friday its Leismer project was producing 13,000bpd, up from 9000bpd two days before.
Imperial Oil has said it had restarted limited operations at its Kearl site, with a capacity of 194,000bpd.
A ConocoPhillips Canada spokesman said the company was "cautiously optimistic" but gave no time frame on restarting operations.
Still many operations remained shut due to the blaze, which comes on the back of a two-year slump in global crude prices.
Syncrude told customers to expect no further crude shipments for May, trading sources said on Thursday.
On Friday officials said the Suncor and Syncrude oil sands sites remained under mandatory evacuation orders along with 19 work camps north of Fort McMurray.
Some of the 90,000 evacuees who fled as the inferno breached Fort McMurray this month may be allowed to return by June 1, if air quality improves and other safety conditions are met.