Tokyo: Japan may start drilling near a gas field in disputed waters of the East China Sea if China does the same, the Nikkei business daily reported on Sunday, as territorial tensions between the countries grow.
Japanese Prime Minister Naoto Kan and his foreign minister said Tokyo will take "countervailing steps" if China starts drilling at the Chunxiao gas field to which Beijing recently sent equipment, Nikkei said, adding that Tokyo had looked into possibly taking the case to international maritime court.
The exchange over the gas field is adding to an increasingly testy Sino-Japanese argument about territorial rights in the seas, especially around a group of uninhabited islets called the Diaoyu islands in China and the Senkaku islands in Japan.
The dispute flared earlier this month after Japan arrested the captain of a Chinese fishing boat, following collisions with Japan Coast Guard ships near the islands.
China has repeatedly demanded Japan free the captain, whose detention period is set to expire on Sunday, and has bared its anger by cancelling planned talks with Japan over natural gas reserves.
Japanese prosecutors can hold the Chinese boat captain for up to a total of 20 days, up to September 29, while deciding whether to take legal action.
On Saturday, about a hundred Chinese protesters in several Chinese cities demanded Japan free the boat captain. Police presence was still heavy at the Japanese embassy in Beijing on Sunday but there were no signs of protests.
The two countries are at odds over China`s exploration for natural gas in the East China Sea, while Beijing is also involved in territorial disputes with Southeast Asian nations in the South China Sea over an area rich in energy and key to shipping.
The Sino-Japanese row centres on where the boundary between the two sides` exclusive maritime economic zones falls. In 2008, the two countries agreed in principle to solve the feud by jointly developing gas fields.
Estimated net known reserves in the disputed fields are a modest 92 million barrels of oil equivalent, but both sides have pursued the issue because there may be larger hidden reserves.