Labour leader Ed Miliband bowed to complaints yesterday and announced an easing of new rules which would put a huge barrier in the path of potential left-wing leadership candidates.

Mr Miliband said that 15 per cent of MPs would have to nominate candidates - not 20 per cent as originally proposed in wide-ranging constitutional changes.

This would still be an increase on the 12.5 per cent of MPs at present required to nominate candidates for the leadership or deputy leadership.