Canadian energy company Nexen said it was reviewing the fire situation in Alberta, but keeping its facilities shut down until it was able to reach its oil facilities.

More than 90,000 people have registered with the regional Red Cross following mass evacuations of Fort McMurray, a region central to Alberta's oil sands operations. Alberta Premier Rachel Notley said more than 2,000 structures were lost to the fires.

"It's not yet safe to return," she said late Monday.

Nexen, a subsidiary of a larger Chinese oil company, said in a statement it was donating to the Canadian Red Cross in a trend that followed appeals from the Canadian Association of Petroleum Producers. Its oil facilities in the region, however, remain closed.

"Nexen is in contact with the provincial emergency response team and has received reports on the fire situation, but until we gain access to our site, the status of our facility is still unknown at this time," the company said in a statement.

Suncor, one of the larger operators in the region, said it was reassessing the situation as the fires move east away from its facilities. Provincial authorities said the fire conditions remain extreme and the Fort McMurray wildfire, which encompasses more than 750 square miles, is expected to grow Tuesday as it makes its way toward the provincial border with Saskatchewan.

Producer Syncrude, meanwhile, said it was calling on its Fort McMurray-based employees to not report to work unless a specific request is made, though it was reviewing its access options to restore operations.

"As our restart plans are finalized, the appropriate employees will be contacted directly and instructed on next steps," the company said in a statement.

Alberta oil producers said they plan to revamp their strategies after meeting with Notley.