Liberal Democratic Party factions led by Prime Minister Keizo Obuchi and former party Secretary General Koichi Kato separately opened election campaign headquarters in Tokyo Wednesday for next month's party presidential race.

Kato's group, which currently includes 70 Diet members, opened its campaign office for the presidential bout inside his group's headquarters in Akasaka, Minato Ward, while Obuchi's set up shop at the Akasaka Prince Hotel.

As the group opened the office, Kato said, "I feel honored to be able to run for the election, but at the same time, I fully realize the grave responsibility."

"I want Japanese people to regain their confidence and I hope to convey this message through my election campaign," he said.

Although Obuchi, who is in the hospital for a medical checkup, was not present to mark the launch of his campaign office, faction Chairman Tamisuke Watanuki told the group's members that they will cooperate with other groups within the LDP, which have already expressed support for Obuchi.

Obuchi's faction, which has 94 Diet members, plans to jointly open another campaign office in the same hotel with other groups including one led by LDP Secretary General Yoshiro Mori and another headed by former Construction Minister Shizuka Kamei as early as next week.

Another contender, Taku Yamasaki, former head of the LDP's Policy Affairs Council, set up his election campaign headquarters last week.

Before the election on Sept. 21, the three will travel across the nation giving their policy speeches and trying to gain LDP members' support.