Embattled Japanese Prime Minister Shigeru Ishiba will resign to avoid a split within his ruling party, a source close to the premier said on Sunday, pitching the world's fourth-largest economy into fresh political uncertainty. A spokesperson for the Prime Minister's Office did not immediately have a comment when contacted by Reuters, but the government said Ishiba would hold a press conference at 6 pm (0900 GMT). Since the former defence minister came to power in September last year, his coalition has lost its majorities in elections for both houses of parliament amid voter anger over rising living costs. He had refused calls from within his Liberal Democratic Party - which has ruled Japan for almost all of the post-war era...