Japan's incoming prime minister, Shigeru Ishiba, said he wanted to clean up his ruling party, revitalise the economy and see off security threats from powerful neighbours after triumphing in his fifth and what he called final leadership bid on Friday.

Former Defense Minister Shigeru Ishiba, a plain-spoken populist, won leadership of Japan’s ruling Liberal Democratic Party in a runoff vote on Friday.

Japan ’s former defence minister, Shigeru Ishiba, has won the ruling Liberal Democratic Party’s (LDP) presidential election at his fifth and final attempt, defeating economic security minister Sanae Takaichi in a runoff vote.