Prime Minister Yoshiro Mori may resign before the opposition camp submits its no-confidence motion against his Cabinet this evening, a senior member of the Democratic Party of Japan said Sunday.

In a speech at Seikei University in western Tokyo, DPJ Secretary General Naoto Kan said, "There is a possibility that Prime Minister Mori may give up before the submission" of the no-confidence motion planned by the DPJ and three other opposition parties.

Kan said Koichi Kato, a former secretary general of the ruling Liberal Democratic Party who set off the revolt against Mori, should leave the LDP if he is serious about changing Japanese politics.

Kato heads the LDP's second-largest faction, which has 45 members in the House of Representatives. He asked Mori to step down two weeks ago and has said he will support the opposition camp's no-confidence motion.

He said neither the LDP nor Japanese politics as a whole would change if Kato stays in the party and tries to succeed Mori as LDP president, and thus, prime minister.

In a speech to an audience packed with some 700 students, parents, faculty and residents, at the private university in Musashino, Kan said his party is working on legislation to limit the central government's powers to foreign policy, defense, crisis management, welfare and other vital sectors.

The essence of the measure is "a return to the Edo era," when feudal clans across Japan were responsible for schooling, police and other local affairs, Kan said.

Meanwhile, Social Democratic Party leader Takako Doi said Sunday at a lecture hall in Tokyo that the opposition camp will have a good chance of toppling the ruling coalition if a snap election is called.