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.

Labour's national executive approved former general secretary Lord Collins proposed changes by 28 to two yesterday with one abstention.

Only MP Dennis Skinner and Christine Shawcroft voted against.

Trade unionists on the executive voted in force for the changes, including bitterly controversial proposals to weaken the historic link between the party and the unions.

The new rules will require trade unionists to opt in individually as affiliated members, instead of the existing arrangement where unions sign up large numbers of members en bloc.

It is a huge leap in the dark, with no clear indication of how many trade unionists will pay £3 to sign up.

Labour deputy leader Harriet Harman hopes that around 270,000 trade unionists will sign up - compared to the current affiliated union membership of around 2.7 million.

nThe liberal Guardian newspaper yesterday raked up the stale row over Labour's Falkirk selection by leaking an internal report.

A Labour spokesman said: "We have selected a candidate, and we have now moved on."