OSAKA -- Two ships that will transport mixed plutonium-uranium (MOX) fuel currently stored in Takahama, Fukui Prefecture, back to England began their journey to Japan on Friday, Kansai Electric Power Co. Ltd. officials said Friday.

"The Pacific Pintail and Pacific Teal departed Britain this morning," said Yuichiro Matsuo, an official at Kepco's nuclear fuel division. "It will take the two ships between one and two months to arrive in Japan."

The fuel the ships will carry was originally delivered to a Kepco-operated nuclear power plant in Takahama in October 1999 by British Nuclear Fuels Ltd.

However, after antinuclear activists in Britain and Japan voiced concerns over anomalies in the MOX fuel's quality control data, BNFL admitted that the data had been falsified and Kepco, bowing to public criticism, decided not to use the fuel.

Kepco said final preparations are under way concerning the loading of the fuel onto the ships. However, the firm would not reveal the ships' route, citing security concerns.

Greenpeace and other antinuclear activists have expressed concerns that the fuel will be loaded onto the ships in June -- a time when Japan and South Korea will be jointly hosting the World Cup soccer finals and concern in the region over potential terrorist threats will hit new heights.

Kepco officials would not reveal whether the ships would arrive during the World Cup or the exact date when the fuel would be loaded on board, saying only that no final decisions have been made.