Yukio Hatoyama is considering his future as leader of the Democratic Party of Japan amid mounting DPJ dissent over the party's dismal performance in recent by-elections, a senior party member said Monday.

"Hatoyama is seriously considering the current situation," said DPJ Special Representative Tsutomu Hata. "In order to resolve the situation, Hatoyama strongly believes he has to take some action."

Hata was referring to calls for Hatoyama to voluntarily step down after the party won just one of the seven seats contested on Oct. 27.

"The party was defeated in the elections and its support rate" is falling, remarked Hata.

Hata appeared to be urging agitated junior DPJ lawmakers to stay calm and give Hatoyama time to make his own decisions on the matter.

The DPJ is the nation's largest opposition force.