Robin Cook's modernisation of the Houses of Commons hit a setback last night amid claims of dirty tricks by Conservative and Labour whips.

MPs unexpectedly voted against reforms to the Commons select system - proposals that diminished the role of party whips in the selection of committee members.

The setback, which followed a row and revolt over government whips attempts to remove independent-minded committee chairmen, have triggered a row over the role of Labour's whips during a free vote.

Some Labour MP allege that government whips sabotaged reforms strongly associated with the Commons leader.