A group of traditional owners from the Northern Territory have filed human rights grievances against 15 banks over their $1bn loan for a major offshore gas project.

Environmental organisations and traditional owners from the Tiwi Islands have been campaigning against the $3.6bn Barossa gas project run by energy giant Santos.

Traditional owners had a major win last year when a judge found Santos had failed to properly consult them over the project which would have seen a gas pipeline installed through their sea country.

Now, six Tiwi Island traditional owners and one Larrakia traditional owner have filed human rights grievances against both Australian and international banks calling on them to withdraw from funding the project.

Equity Generation Lawyers, which is representing the group, said it had asked the recipients – which include ANZ, NAB, Westpac and CBA – to respond by May 16.