The Social Democratic Party doesn't have a future and should consider disbanding and uniting with other opposition forces to create a united front to protect the war-renouncing Constitution and rid Japan of nuclear power, said former Prime Minister Tomiichi Murayama, who remains an SDP member.

"Parties should join hands on issues like (opposing plans to) amend the Constitution that would decide the fate of the nation, and create a single party," Murayama said Sunday on moves by Prime Minister Shinzo Abe and his ruling Liberal Democratic Party to go after war-renouncing Article 9.

He said the SDP can offer its nationwide network of local chapters to support a campaign to form a unified opposition bloc to counter the LDP.

Earlier in the day, Murayama said on a TV program that it is important to create an opposition force that will keep the LDP's "monopoly" in check until the next Lower House election.

He also criticized Abe for omitting words of remorse for Japan's wartime aggression during the ceremony last Thursday to mark Japan's surrender in World War II.

In the 1990s, as prime minister, Murayama issued a war apology that used terms like "remorse" — wording that subsequent prime ministers, including Abe from 2006 to 2007, annually voiced.