Sepp Blatter says he will resign as president of football's governing body Fifa amid a corruption scandal.

In announcing his exit, the 79-year-old has called an extraordinary Fifa congress "as soon as possible" to elect a new president.

Blatter was re-elected last week, despite seven top Fifa officials being arrested two days before the vote as part of a US prosecution.

But he said: "My mandate does not appear to be supported by everybody."