Prime Minister Naoto Kan on Saturday began considering specific countermeasures in the event China commences drilling at a disputed gas field in the East China Sea, Japanese government sources said.
Possible countermeasures include a plan for Japan to conduct its own test drilling in the sea near the Chinese offshore facility under development at the gas field, over which both Tokyo and Beijing have claimed exploration rights, the sources said.
The move comes after aerial photographs taken by the Self-Defense Forces show that China has recently transported what appears to be drilling equipment to the facility, now known in Japan as Shirakaba and in China as Chunxiao, the sources said.
Kan met with Foreign Minister Seiji Maehara, Chief Cabinet Secretary Yoshito Sengoku and other officials at his official residence Saturday to discuss how to react if China begins gas extraction work.
They reaffirmed that the Japanese government will continue to closely watch China's moves and urged Beijing to exercise self-restraint through diplomatic channels, the sources said.
Japan plans to reinforce surveillance with P-3C patrol aircraft in the area.