Tokyo - The discovery of old pottery shards and artefacts on the southern Japanese island of Okinawa could delay relocation work for a US military base, officials said Friday, the latest twist in a long-running battle over the unpopular project.
Japan and the United States have been struggling for nearly 20 years to realise a plan to move a US Marine air facility in a densely populated city in the central part of the island to a remote beachside location in the North.
But resistance to the plan has been fierce on Okinawa, the site of a bloody World War II battle where officials and residents complain the crowded island bears too heavy a burden in hosting US military bases.
An official in the city of Nago, where the new base is under construction told AFP that several fragments from clay pots as well as a stone used in a ship's anchor dating back several hundred years have been found.
"We are preparing to seek Okinawan government authorisation" to declare the area where the artefacts were found "an archaeological site," the official said.
The anchor piece, found offshore in February, has already been registered as a cultural property, he said. That discovery led to a more detailed search in which other fragments emerged.
If the site is authorised as having archaeological significance the local office of Japan's defence ministry, which ordered the construction of the new base, must take steps such as carrying out further study which "may delay the plan", said the official, although it is unclear for how long.
Officials at US Marine Camp Schwab in Okinawa could not immediately be reached for comment.
The news comes after the Japanese government last month overturned a move by Okinawan Governor Takeshi Onaga to stop construction work.
Tokyo's decision means that efforts to move the base from the residential area in the city of Ginowan to the secluded Henoko district of Nago would continue, though the discovery of the artifacts could at best delay it, Okinawan officials said.
Chief Cabinet Secretary Yoshihide Suga when asked about the discovery suggested that the government would respect legal procedures covering the handling of artefacts.
"We will deal with the issue appropriately based on law," he told reporters Thursday.
The proposal to relocate the Futenma air base, first mooted in 1996, has increasingly become the focus of anger among locals, who insist it should be shut down and a replacement built elsewhere in Japan or overseas.
Residents have long complained of aircraft noise as well as crimes and accidents involving US troops, stressing that the rest of Japan must share the burden of hosting the bases.
Okinawa, which accounts for less than one per cent of Japan's total land area, is home to about 75 per cent of US military facilities in the country.
Tokyo and Washington have repeatedly backed the relocation plan, with Japanese Prime Minister Shinzo Abe calling it "the only solution".