Gordon Brown, prime minister, has come under fire for his 'indefensible' decision to sanction the payment tomorrow of bonuses to staff at Northern Rock, the nationalised bank.

Employees will get a bonus worth 10% of their salary under a scheme designed to reward fast progress in paying back the taxpayer loan, which was made when the bank was nationalised last February to keep it afloat.

Northern Rock said yesterday that the 'vast majority' of staff would benefit from the scheme but declined to detail the total amount being paid out.

Financial Times