Dozens of nationalist protesters have confronted movie-goers in Tokyo amid anger about a documentary which chronicles the slaughter of dolphins in a western Japanese village.

A handful of Tokyo cinemas are screening the Oscar-winning documentary The Cove, which includes graphic footage of dolphins being herded into shallow water near the village of Taiji.

Some of the mammals are kept alive to be handed over to aquariums, while the rest are harpooned.

Many theatre operators decided not to screen the film amid the threat of protests from right-wing demonstrators, who accuse the filmmakers of being "anti-Japanese" and of poisoning Japanese minds.

But not everyone bowed to the threats.

Some have decided to confront a subject few in Japan know anything about.

"The killing and eating of dolphins is happening in this country," movie-goer Tetsushi Matsuoka said.

"But most Japanese don't know much about it. This is why I've come to see this film."

While some like Mr Matsuoka came to see The Cove, others had come to stop movie-goers from watching it.

Several dozen nationalists waved banners and screamed through loudspeakers outside a theatre in the Tokyo district of Shibuya.

They were angry at what they saw as the latest example of Japan-bashing.

At one stage scuffles broke out and police moved in to keep protesters and movie-goers apart.

Holding a sign reading "Stop Racial Discrimination Against Japanese" demonstrator Nobuo Kikuchi took a shot at what he said was Australian hypocrisy.

"Australia kills 3 million kangaroos a year, but no-one does anything about that," he said.

"What I want to know is why the Japanese have become a target? That needs to be debated internationally."

But to others in Japan, the protesters are about stifling debate rather than promoting it.

"The very act of exerting this sort of pressure is intimidation," movie-goer Masaki Iwaji said.

"This infringes on people's freedom of expression. It doesn't matter what's in the film."

Whether it is a movie about a dolphin hunt or international criticism about Tokyo's so-called scientific whaling program, many protesters believe Japan is being assailed by the West and pressured to abandon what they see as their country's traditions.