South African Archbishop Desmond Tutu is scheduled to appear at a conference in northern Alberta to discuss aboriginal treaties and the oilsands.

The Nobel laureate, who has taken strong stands on climate change and against projects such as the Keystone XL pipeline, is to appear with industry and political leaders at a two-day event that begins May 31 in Fort McMurray.

"He has been vocal about his position on the oilsands," said Eriel Deranger, spokeswoman for the Athabasca Chipewyan First Nation, which is co-sponsoring the conference.

"He's really brought forward the moral imperative question about can we really move forward with these projects knowing what we know now? I really hope that he can bring this moral imperative narrative to discussions about Alberta's tar sands."

The other sponsor is Toronto law firm Olthuis Kleer Townsend, in which former Ontario premier and one-time federal Liberal leader Bob Rae is a partner. Rae is to be one of the speakers, who also include former Northwest Territories premier Stephen Kakfwi and former Syncrude Canada president James Carter.

Conference to address treaty relationships

The title of the conference is As Long As the Rivers Flow: Coming Back to the Treaty Relationship In Our Time. It's intended to discuss the need for renewal of treaty relationships in light of extensive resource development such as the oilsands.

"We are proud to host a moral leader like Archbishop Tutu, who has done such important work for his people in his own country," said Athabasca Chipewyan Chief Allan Adam.

"We hope he can guide us to open a conversation with Canadians about the current state of treaty relationships, and how we can move forward together, understanding our respective obligations."

Deranger said federal and Alberta government officials have been invited. She couldn't say if any will attend or speak.

Tutu, 82, has been outspoken against oilsands development. In an opinion column earlier this month in the British newspaper the Guardian, he called the Keystone XL pipeline proposal to move oilsands bitumen from Alberta to the U.S. "appalling."

His article speaks about a religious responsibility to fight against climate change.

History of speaking out against oilsands development

"It is a responsibility that begins with God commanding the first human inhabitants of the Garden of Eden to 'till it and keep it.' To keep it, not to abuse it, not to destroy it."

Tutu has signed a petition against the pipeline. He has called for boycotts of events sponsored by the fossil fuel industry, health warnings on oil company ads and divestment of oil industry investments held by universities and municipalities.

Tutu suggested the Keystone XL pipeline could increase Canada's carbon emissions by 30 per cent.

The Anglican leader and human rights icon, who was a central figure in South Africa's successful fight against apartheid, is the latest high-profile critic to visit the oilsands city.

Earlier this year, musician Neil Young played concerts in several cities to support the Athabasca Chipewyan after he visited the region. In 2010, Hollywood director James Cameron toured the oilsands and the community of Fort Chipewyan.