Caroline Kennedy, Yoko Ono Speak Out Against Japan's Dolphin Cull in Taiji Cove

The US Ambassador to Japan and Yoko Ono, the wife of legendary Beatles frontman John Lennon, have added their names to the growing list of high-profile opposition to Japan's annual dolphin cull in the rural town of Taiji.

Friday, Ambassador Caroline Kennedy said in a tweet that the US government opposed the annual "drive hunt" and that she is concerned about the issue.

"Deeply concerned by inhumaneness of drive hunt dolphin killing," Kennedy wrote. "USG opposes drive hunt fisheries."

A drive hunt refers to the practice of corralling dolphins into a cove or otherwise inescapable area, where they can be trapped or killed.

Japan's whaling and dolphin-hunting programs have long been a controversial subject, and the nation frequently faces criticism for the practice. Japan, however, claims that hunting marine mammals is part of its cultural heritage.

Japan's Chief Cabinet Secretary Yoshihide Suga told reporters Monday that the Taiji dolphin cull was done in accordance with Japanese laws.

"Dolphin fishing is a form of traditional fishing in our country," he said, according to The Associate Press, which reported he was responding to a question about Kennedy's criticism. "We will explain Japan's position to the American side."

Known for her work as an artist and peace activist, Ono, who was born in Tokyo, said the annual dolphin-hunt - which was brought to worldwide attention in the 2009 Academy Award-winning documentary "The Cove" - provides an opportunity for other nations to speak ill of Japan.

"I am sure that it is not easy, but please consider the safety of the future of Japan, surrounded by many powerful countries which are always looking for the chance to weaken the power of our country," Ono said in an open letter published on her website.

"At this very politically sensitive time, [the hunt] will make the children of the world hate the Japanese," she said.

Since it was published Monday, Ono's letter has spread across the Internet and drawn praise, including that of eco-activist Paul Watson, who is founder of the Sea Shepherd Conservation Society.

The conservation group, viewed by some as radical, is in opposition to the hunt and first reported that last weekend more than 250 dolphins, including a rare albino dolphin calf, were herded into Taiji's cove, where the prettiest of the lot would be taken and sold to aquariums and many of the others killed for meat.

In a blog post Sunday, Watson said, "Capturing dolphins for display in aquariums is not part of Japanese culture and the brutality of this slaughter would never be legally accepted in any abattoir in the world including Japan."

Watson said dolphins are highly-intelligent, complex animals and that there is no moral or cultural justification for killing them now that we know as much about them as we do now.

"In the name of human decency and for the sake of all future generations this shameful crime against nature and humanity must end," he said.