After two weeks of deliberations, a criminal court in Puyo, Ecuador, accepted a Waorani tribe bid for court protection in Pastaza province to stop an oil bidding process. Photo: AFP / Rodrigo BUENDIA

Ecuador's Waorani indigenous tribe won their first victory Friday against big oil companies in a ruling that blocks the companies' entry onto ancestral Amazonian lands for oil exploration activities.

After two weeks of deliberations, a criminal court in Puyo, central Ecuador, accepted a Waorani bid for court protection in Pastaza province to stop an oil bidding process after the government moved to open up around 180,000 hectares for exploration.

The lands are protected under Ecuador's constitution that establishes the "inalienable, unseizable and indivisible" rights of indigenous people "to maintain possession of their ancestral lands and obtain their free adjudication."

Crucially, however, the wealth in the subsoil is owned by the state.

The constitution also enshrines the need for prior consultation on any plans to exploit the underground resources, given the probable environmental and cultural impacts on tribal communities.

The state reached an agreement with the Waorani over oil exploration in 2012, but the tribe's leaders say they were duped.

The judges ordered the government to conduct a new consultation, applying standards set by the Inter-American Court of Human Rights, based in San Jose.

The ruling "has created a significant precedent for the Amazon," said Lina Maria Espinosa, attorney for the plaintiffs, outside court.

"It has been demonstrated that there was no consultation and that the state violated the rights of this people, and therefore of other peoples."

The Waorani, who number around 4,800, also inhabit other Amazonian provinces.