Six containers of whale meat are on their way back to Iceland after German authorities removed the controversial cargo from a ship bound for Japan, Icelandic media reported on Friday.

The batch was first stopped by German customs in Hamburg, where the containers were unloaded and then sent back via Rotterdam in the Netherlands.

Samskip, a Netherlands-based shipping firm involved in the original transit of the containers from Iceland to Rotterdam said it would not ship any more whale meat, agreeing to let another firm handle the return journey.

"A formal request was made by the Port of Rotterdam to all carriers to cease transit of whale meat through the port. Samskip advised the port that it would comply," the shipping group said in a statement.

It added that Samskip "does not plan to ship whale meat in the future."

The refusal to transport whale meat will likely be hailed as a victory by environmental groups opposed to whale hunting.

Iceland's public broadcaster RUV on Friday said the meat was on its way back to the North Atlantic island.

"Transportation of products between Iceland and Japan is in accordance with international law," Foreign Minister Gunnar Bragi Sveinsson told RUV.

Iceland "will now consider how to react to the transport of whale products being stopped and will stand firmly on Icelandic interests in this matter," he added.

Iceland resumed its disputed commercial fin whale hunt in June.

Hvalur, the only company that hunts the giant mammals, killed 148 fin whales in 2010, but none in 2011 and 2012 due to the disintegration of its only market in quake- and tsunami-hit Japan.

The country also hunts minke whales, a smaller species.

The International Whaling Commission imposed a global moratorium on whaling in 1986 amid alarm at the declining stock of the marine mammals.

Iceland and Norway are the only two countries still openly practising commercial whaling in defiance of the moratorium.

Japan also hunts whales but insists this is only for scientific purposes even if most of the meat ends up on the market for consumption.