Japan's Prime Minister Shinzo Abe has announced he is stepping down. His resignation brings to an end a year in office marred by a string of scandals and a humiliating electoral defeat in Japan's upper house of Parliament.

As a result, he said it was now difficult to push ahead with the effective policies that won the support of the public. 

So far, no date has been set for his departure. 

However, even at this early stage, Mr Abe's former foreign minister, Taro Aso, has been tipped as one of the front-runners to replace him.