The bail-jumping Sea Shepherd leader, Paul Watson, is embattled on a new front, with the group's former boat skipper, New Zealander Pete Bethune.
Apparently hiding out at sea, Mr Watson claims Mr Bethune gave evidence that would have let Japan mount the prosecution to extradite him from Germany, had he not fled.
Mr Bethune rejected blame and instead said he was claiming $US500,000 ($476,000) from Sea Shepherd over his sunken vessel, Ady Gil.
After being detained for nearly three months in Frankfurt pending extradition to Costa Rica on navigation charges, Mr Watson disappeared on 22 July, forfeiting €250,000 ($293,000) bail.
In a message through his group's headquarters, Mr Watson told supporters he is now "in a place on this planet where I feel comfortable, a safe place far away from the scheming nations who have turned a blind eye to the exploitation of our oceans".
A senior attorney in the Frankfurt Attorney-General's office Guenter Wittig confirmed to Fairfax Media that his office had received a Japanese request for Mr Watson's extradition, and had issued a warrant for his arrest.
Japan's chief cabinet secretary, Osamu Fujimura, said his government wanted to hold Mr Watson for further investigation.
Sea Shepherd and the Japanese government are preparing for renewed conflict this coming summer over its Antarctic "research" whaling.
Mr Watson said the extradition order to Japan relied on fabricated evidence provided by Mr Bethune, who boarded a Japanese whaling ship in 2010 seeking restitution after it sliced his boat Ady Gil in two.
"He co-operated to provide false evidence to the Japanese Coast Guard to blame me for the boarding actions, despite the on-camera documentation that I specifically advised against the boarding," Mr Watson said.
Mr Bethune, who now heads his own Earthrace Conservation organisation, told Fairfax: "Paul needs to stop blaming me for his problems. He has been battling Japan's whalers for years in Antarctica, and they have a mountain of evidence against him."
Mr Bethune said it was no secret that Mr Watson headed Sea Shepherd, that he was the captain of the Steve Irwin, and he had been very effective in standing up to Japan's whaling.
"To then blame his current predicament on my testimony from two years ago is crazy. I'm surprised he's not blaming me for his problems with Costa Rica as well. And when his car breaks down."
Mr Bethune said an arbitration hearing had begun this week in Annapolis, Maryland, into his claim for $500,000 that he said Sea Shepherd owed him over the initial purchase of the Ady Gil.
"I am looking forward to seeing an end to it all and being able to concentrate on the mountainous challenges to our marine environment rather than my mountainous debts,” Mr Bethune said.
Mr Watson indicated that, despite his predicament, he still planned to go south for his ninth campaign against the whalers.
"The campaign will be called Operation Zero Tolerance, and we will risk our ships and ourselves yet again in the effort required to stop these pelagic bandits in their remorseless slaughter of the gentle giants of the seas."
Former Australian Greens leader, Bob Brown, said the federal government should offer political asylum to Mr Watson.
“No one on earth has done more to protect Australia's whales from the illegal slaughter of the Japanese fleet than Paul Watson. He should be honoured, not hounded,” said Dr Brown, who is about to co-lead a Sea Shepherd campaign against the James Price Point gas hub in Western Australia.