TOKYO - ACTIVISTS prepared large protests to meet the arrival of the USS George Washington aircraft carrier, which is to dock just south of Tokyo on Thursday to become the first nuclear-powered carrier with its home port in Japan.

Organisers said on Monday they planned to hold demonstrations throughout the day, both onshore and on boats in the harbour around the US naval base at Yokosuka, where the George Washington carrier is to arrive.

'Having a nuclear-powered carrier based in Yokosuka is like having a nuclear power plant built right next to our capital, said Ms Masahiko Goto, a local lawyer who has led opposition to the deployment.

Ms Goto said a few hundred people were expected to join in protests as the ship arrives, and another 2,000 were to gather near the base that night.

The George Washington aircraft, which can carry a crew of up to 5,600 and 70 aircraft, will replace the USS Kitty Hawk as the US Navy's only permanently forward-based aircraft carrier.

The Navy has said the deployment of the carrier demonstrates America's commitment to providing 'the most advanced capabilities' to the US 7th fleet, which is home-ported in Yokosuka.

The decision to base the George Washington in Yokosuka has also been welcomed by Japan's government.

Along with the 7th Fleet, about 50,000 US troops are deployed throughout Japan under a mutual security pact. But the arrival of the new carrier has been controversial because it will mean more sailors will be based in Yokosuka and also because of concerns of a possible accident or leakage from its nuclear reactor.

The Kitty Hawk, which is to be decommissioned, was conventionally powered.

Concerns over safety were heightened when the US Navy disclosed in early August that the USS Houston, a submarine, had leaked water containing radiation during several calls to Sasebo and Okinawa, in southern Japan, and Yokosuka between July 2006 and April 2008.

A Navy investigation found the leak posed no danger to Japan. -- AP