Why has Japanese PM Shinzo Abe called an election?

Japan's Prime Minister Shinzo Abe has called an early election, two years ahead of schedule.

At a news briefing, he said he would dissolve parliament later this week and was also delaying a planned but unpopular increase in sales tax.

Mr Abe was elected two years ago with an ambitious plan to revive the economy, but has struggled to do so.

The BBC's Rupert Wingfield-Hayes said that Mr Abe may be looking for a mandate from the Japanese people to "push ahead with even bolder economic reform next year".