The US arm of anti-whaling group Sea Shepherd has agreed to pay $3.332 million dollars to Japanese whalers for breaching a court injunction.

In 2012, The US Ninth Circuit Court of Appeals issued an injunction ordering Sea Shepherd to remain at least 500 yards (about 450 metres) away from Japanese whaling vessels in the Southern Ocean, near Antarctica.

Sea Shepherd then withdrew from its anti-whaling operations in the Southern Ocean.

In February 2013 the court ruled Sea Shepherd's activities amounted to piracy and it had breached its injunction.

In a statement on its website Sea Shepherd said a third party vessel had breached the court injunction.

... other foreign, independent entities that also use some form of the "Sea Shepherd" name came within 500 yards of ICR's vessels during Operation Zero Tolerance.

Legal proceedings continued in American courts, with Sea Shepherd USA filing a petition to the Supreme Court asking it to review the decision earlier this year.

Sea Shepherd has now agreed to pay the US$2.55 million to the whalers to resolve the matter.

The payment will be received by the Institute of Cetacean Research (ICR) and Kyodo Senpaku, the two main bodies behind Japan's whaling program.

While Japan claims the whaling program is for research, the International Court of Justice last year ruled it was not designed for scientific purposes, and ordered it be ceased.

Sea Shepherd's board president Ethan Wolf said the group did not agree with the court's finding but would pay the whalers the fine.

He said it would not be paid from donations received from supporters.