Shell has dismissed shareholder calls for a review of its controversial oil sands developments.

A group of institutional investors, led by campaign group FairPensions, had tabled a special resolution ahead of the Anglo-Dutch company's annual meeting next month. They want Shell to review the commercial and environmental viability of going ahead with its new projects in Canada's boreal forests.

But the Anglo-Dutch oil company today urged other investors to vote down the resolution. "Whilst the issues raised by the group of shareholders ... are valid and appreciated ... it would set a precedent which, if applied more generally to the company's major investment opportunities, would add unnecessary costs and duplication of effort."

The letter to shareholders, giving notice of the meeting in the Hague on 18 May, added that the company had already provided all the non commercially sensitive information to shareholders about its oil sands projects. BP, whose annual meeting takes place on Thursday, is facing similar pressure from shareholders over its own oil sands activities.

Shell's next development phase of its Athabasca joint venture will soon add 100,000 barrels per day. This will take production from oil sands mining to 4% of its total production. About 0.6% of its current production comes from in situ operations, where the oil is recovered from beneath the ground by drilling.

The campaign led by FairPensions, whose supporters include the Co-operative and trade union Unison, argue that the projects are too big an environmental and economic liability. They also argue that climate change caused by oil sands development could put at risk shareholders' other investments.

The issue of oil sands has soared up the political and environmental agenda since the Copenhagen summit highlighted the need for a clampdown on carbon-intensive activities.