Environmental group Sea Shepherd will not use money from donations to pay a $3.54 million settlement to Japanese whalers, it says.
Sea Shepherd reached the settlement to resolve civil contempt charges after breaching an American court injunction to stay clear of Japanese whaling vessels in the Antarctic Ocean.
Sea Shepherd said in a statement on its website it had abided by the injunction forcing it to stay at least 450 metres away from whaling vessels, but other independent groups did not.
Sea Shepherd board president Ethan Wolf said it disagreed with the contempt finding but would pay up.
The fine would be paid from money from other legal actions and settlements, he said.
Sea Shepherd lawyer Claire Davis said it attempted to appeal against the decision to the US Supreme Court.
She said that court only heard about 1 percent of the appeals it was asked to hear and chose not to in this case - so Sea Shepherd must pay, whether it agreed with the decision or not.