However crushing a verdict the voters deliver on the Labour party in Thursday’s local and European elections, this week’s spectacle of Gordon Brown’s ministers voting with their feet is so profoundly undermining as to call into question the UK prime minister’s future.

Mr Brown has a slim chance to assert his authority and restore some backbone to his invertebrate party. If he fails, the answer is not another palace coup. The voters have the right to choose their new government at a general election.