A small First Nations group from Alberta has lost its chance to pursue a land claim over most of south Edmonton after Canada's top court said too much time had passed to proceed.

The group, claiming to be descendants of the Papaschase First Nation, cannot go ahead with a class-action lawsuit against the federal government, the Supreme Court of Canada ruled unanimously Thursday. 

Members of the Papaschase Descendants Council had argued their ancestral lands — about 130 square kilometres south of Edmonton — were illegally taken by the federal government in 1888. The group wasn't seeking a return of the lands, but about $2.5 billion in compensation.

Papaschase Chief Rose Lameman told CBC News the decision was "certainly a blow," though not unexpected.

"I was expecting it, but I was praying and hoping that the Canadian government and judicial system and the Canadian people would come to the realization that something has to be done about Canada's aboriginal people," she said.

Lameman said she believes there are still other avenues that can be explored with the federal government and internationally.

In its 7-0 ruling, the court said a group of Papaschase descendants indicated in 1974 they planned to proceed with a land claim "in the near future."

With Alberta's statute of limitations set at six years, the court ruled too much time had passed for it to consider a land claim.

"Were the action allowed to proceed to trial, it would surely fail on this ground," the court wrote.

A historic wrong, lawyer says

Eugene Meehan, the lawyer who represented the Papaschase First Nation descendants, said the high court missed a crucial chance to correct a historic wrong.

"There is no middle ground between the right thing to do and the wrong thing to do," he said in an interview. "There is no statute of limitations on the right thing to do. The bottom line is this: a treaty is an ongoing obligation and a breach of a treaty is an ongoing breach."

The group said their ancestors were cheated out of their land in the late 1880s when federal agents offered band members scrip — certificates that could be redeemed for cash — in exchange for land.

With bison hunted almost to extinction and widespread starvation, band members gave up their treaty rights for the scrip, said the group.

But lawyers for the federal government argued the chief of the band at the time sent a telegram to Ottawa demanding a deal and scrip.

"The facts are shrouded in the mists of time and some details are disputed," wrote the top court.

In 2001, Lameman and four other plaintiffs sued the government, alleging that band members were never properly warned of the consequences of taking scrip, that they'd been wrongfully pressured by settlers to give up their land, that it was never legally surrendered and that cash from its sale was mismanaged.

A Court of Queen's Bench Justice ruled against them in 2004. They took the case to the Alberta Court of Appeal and won in 2006, but the federal Justice Department took the case to the Supreme Court of Canada.

Meehan said the ruling will have consequences for other land claims across the country.

"This case will be a hammer that the Supreme Court has given to government to nail down other potential litigation in the aboriginal area on the basis that even major cases, test cases, need not go to trial, that they can be disposed of in a summary way without a single aboriginal witness being heard from, which is what happened here," he said.

With files from the Canadian Press