By George Nishiyama

TOKYO, March 13 (Reuters) Japan's government faces a new headache in talks with the United States about relocating American forces throughout the country after voters in a local referendum overwhelmingly rejected a plan to increase the US presence at a nearby base.

Voters in the southwest city of Iwakuni, home to a US Marine base, by a margin of 8-1 gave a thumbs-down on Sunday to bringing more planes and troops to the facility. The expansion is part of an agreement already reached in talks between Tokyo and Washington.

While the vote is non-binding, the result will complicate plans by the two sides to wrap up negotiations and finalise a comprehensive plan to reorganise the nearly 50,000 US troops in Japan by the end of March.

''The majority 'opposed' vote by the people of Iwakuni is a difficult result for the government, which had envisaged gaining local approval...and releasing a final report at the end of March,'' the Asahi Shimbun, a liberal daily, said on Monday.

''Whether or not to accept the realignment of US troops is a problem all over the country, so the first direct indication of local opinion carries weight.'' More than 43,000 voters rejected the plan while just over 5,000 were in favour, an official in Iwakuni, 600 miles (1,000 km) west of Tokyo, said late yesterday day.

The turnout was almost 59 percent, slightly above 50 percent needed for the referendum to be considered valid, even though the government does not have to abide by it.

Opposition from local communities concerned about noise, accidents and crime associated with US bases has hindered efforts to finalise the overall plan, part of Washington's global strategy to make its military into a more flexible force.

''It is important for central and local government to hold discussions for the good of the country, taking into account the interests of local residents,'' the conservative Yomiuri Shimbun said in an editorial.

NATIONAL VS LOCAL INTERESTS But the paper added that the realignment is aimed at dealing with changing security concerns in the region, including North Korea's nuclear development, China's growing military and the threat of terrorism.

''Iwakuni should not cause confusion by uselessly opposing the government,'' the Yomiuri added.

Situated 350 miles from the border between North and South Korea, US Marine Corps Air Station Iwakuni would play an important role in any conflict involving the peninsula.

But Iwakuni Mayor Katsusuke Ihara, who called the referendum, said residents had the right to be heard.

''This is the voice of the people,'' Ihara told a private Japanese TV broadcaster late yesterday.

''I have no right to comment on national issues such as security, but it is only natural for the people of Iwakuni to speak out on aspects that affect their lives,'' he said.

Japanese government officials suggested the overall plan would be implemented regardless of the referendum.

''It is necessary to carry out the relocation at any cost,'' Defence Minister Fukushiro Nukaga was quoted by Kyodo news agency as saying late yesterday.

The Iwakuni referendum could add momentum to opposition in other communities, including the southern island of Okinawa, home to the bulk of the US forces in Japan.

Okinawa Governor Keiichi Inamine reiterated on Sunday his opposition to a plan to relocate a Marine heliport inside the prefecture.

Besides troop movements, Tokyo and Washington are also discussing how much Japan should pay to move 7,000 Marines to Guam from Okinawa.

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