Japan should revise the five principles under which the Self-Defense Forces can participate in international peacekeeping operations, a senior member of the Liberal Democratic Party said Thursday.

"So long as the so-called five principles remain intact, it will be very difficult for Japan to conduct actual (peacekeeping) activities," said Koichi Kato, a former LDP secretary general and a candidate in the LDP's presidential election.

Responding to questions after a speech in Tokyo, Kato argued that if a United Nations peacekeeping force is organized to stabilize the situation in East Timor, the SDF would not be allowed to participate. This, he said, is because the mission would conflict with the principle of neutrality, as it would be designed to protect those advocating independence.