BP PLC is facing a rebellion from major shareholders over a controversial oil sands project in Canada.

Institutional and individual investors are expected to back a resolution at the company’s annual general meeting on Thursday in London calling for a review of the company’s plans to extract oil from the vast tar sands in north-eastern Alberta.

Campaigners want more detail on the environmental impact, expressing skepticism about BP’s assumptions on future oil demand and carbon emissions.

BP says the project - a joint venture with Canada’s Husky Energy - have the potential to sustain production levels for many decades. It adds that it will mitigate some of the harmful environmental effects and emissions from the oil sands.