Two ships carrying the fuel, a mixture of uranium and recycled plutonium known as MOX, reached Japanese waters in heavy weather as protesters chanted: "Down with nuclear power, down with MOX."
Opposition to the use of the fuel in reactors has been growing since last week when British Nuclear Fuels (BNFL) admitted that records relating to the testing of 11 batches of MOX fuel pellets had been falsified. Anger rose further when Japanese inspectors who had flown to the Sellafield MOX Demonstration Facility, where the fuel is manufactured, found that at least twice that number of tests were faked.
Two ships have been steaming towards Japan carrying MOX assemblies - fuel pellets in rows of zirconium alloy tubes - destined for power plants run by the Kansai Electric Power Company (Kepco) and the Tokyo Electric Power Company (Tepco). BNFL has insisted that these batches were properly tested, but environmentalists are sceptical.
The MOX cargo on The Pintail, one of the ships, is destined for a reactor operated by Kepco in Fukui, north-central Japan.
It is this shipment, which contains MOX from Sellafield, that is causing most concern in Japan. A crowd of protesters gathered outside the Ohkuma plant yesterday despite the weather, chanting anti-nuclear slogans. But strong wind and rain, and a threatened typhoon, accomplished what environmentalists could only hope for, by delaying the unloading, probably until next week.
"Since the waves were toohigh, we have decided to put off our decision to unload on safety grounds," said Kazuya Sugiyama, a spokesman for Tokyo Electric.
The ships are due to sail next week to the west coast of Japan, where, on Monday, the Pacific Pintail will unload 225 kilograms of the fuel for the Kepco plant in Fukui. It will be the first time either firm has used MOX fuel, except in tests.
"It is risky to ship, stock and use this fuel," said Toshihiro Inoue, from the Japan Congress against Atomic and Hydrogen Bombs.
The fuel is highly dangerous and receives the highest security classification. The freighters have a complement of armed guards and carry three 30-millimetre cannons. "Ordinary citizens are very concerned about the safety of nuclear power plants. It is too late if something unpredictable happens," Mr Inoue said.
A Japanese government survey last month found that more than two-thirds of the population were worried about their nation's nuclear plants, with most fearing accidents. When Robin Cook, the Foreign Secretary, was in Japan earlier this month, 35 anti-nuclear groups delivered a protest letter, demanding the shipment be halted and insisting no new reprocessing contracts be signed with Japan.Reuse content