The Liberal Democratic Party might fall to pieces before the next general election because of Prime Minister Taro Aso's plunging popularity, according to an independent lawmaker.

Splinter groups led by lawmakers including Hidenao Nakagawa and Yuriko Koike are already forming, said Lower House member Kenji Eda, who is a visiting professor at Toin University of Yokohama.

The desertions will probably force Aso from office, making him the third prime minister to resign since September 2007, Eda said.

"The general election will be held under a new LDP leader," he said in an interview last week at his office in Tokyo. "The public's turn against the LDP is irreversible."

The formation of splinter groups shows lawmakers don't believe the LDP under Aso can win the next general election, which must be held by September, he said.

"Aso's lack of leadership and public support has turned differences into deep rifts within the party," said Jin Igarashi, a political science professor at Hosei University in Tokyo.