Lawyers for a group of Ecuadorian villagers asked Canada’s High Court on Thursday to grant their clients access to enforce a £6 billion Ecuadorian judgement against oil giant Chevron for rainforest damage.

Lawyers have quarrelled for several years in several countries over who’s responsible for pollution in the rain forest.

The villagers’ lawyers are arguing that the case should be heard in Canadian courts because Chevron has a Canadian subsidiary.

In February 2011, an Ecuadorian judge issued an £11.5bn judgement against Chevron in a lawsuit brought on behalf of 30,000 villagers.

It was for environmental damage caused by Texaco during its operation of an oil consortium from 1972 to 1990.

Ecuador’s highest court last year upheld the verdict but reduced the amount to about £6bn.

Chevron, which now has no assets in Ecuador, has simply shrugged off the case.

The company is being sued because it bought Texaco.

But it insists that a 1998 agreement Texaco signed with Ecuador absolves it of liability.

Chevron claims that Ecuador’s state-run oil company is responsible for much of the pollution in the oil patch that Texaco quit more than two decades ago.

It has also argued procedurally that allowing the action to proceed would violate a principle known as the “corporate veil,” which says that subsidiaries are separate entities from their corporate parents and are not liable for actions of the parents — a convenient legal fiction which allows widespread impunity.