Controversial environmental activist Paul Watson has stepped down as head of the Sea Shepherd Conservation Society after being named in a U.S. court order preventing him from approaching Japanese whaling fleets.  

The Toronto-born anti-whaling crusader, who holds dual Canadian-U.S. citizenship, said he would respect the U.S. Court of Appeals decision issued in December which overturned a prior ruling in Sea Shepherd's favour.

According to the society's website, Japan’s Institute for Cetacean Research (IRC), which Sea Shepherd calls "a front for illegal, government-subsidized whaling," lost a preliminary injunction in the U.S. last February. That injunction sought by the IRC was to stop the society from approaching them in the Antarctic.

"I will respect and comply with the ruling of the United States Ninth District Court and will not violate the temporary injunction granted to the Institute for Cetacean Research," Watson said in a statement.

The latest injunction issued by the U.S. court prevents Sea Shepherd from being within 450 metres of Japanese whaling vessels.

Sea Shepherd's Antarctic whale defence campaign, otherwise known as Operation Zero Tolerance, is organized to curb Japanese whaling fleets operating in the southern ocean.

Interpol arrest warrant

The campaigns against Japanese fleets will continue under the leadership of former Australian senator Bob Brown

Watson's resignation also follows his arrest in Germany last summer on a complaint from authorities in Costa Rica, where he faces charges related to a 2002 protest.

Watson skipped bail, and Interpol later issued an international warrant for his arrest.

In the statement issued Tuesday, Watson maintained his innocence, saying, "I myself have never been convicted of a felony crime."