Greenpeace says further court action against the Government for granting an East Cape oil exploration permit is one of the most important cases it has fought.
The environmental group and Te Whanau-a-Apanui of Bay of Plenty lodged papers in the Court of Appeal on Wednesday arguing the High Court made several errors in law in turning down its challenge.
The High Court last month found the Government was entitled to award a five-year deepwater permit to the Brazilian company Petrobras in the Raukumara Basin.
Greenpeace says it will take the case as far as it can.
It says the two organisations have a solid case and are not taking the action for the publicity.