Charles Kennedy has attacked the government over the cost and effectiveness of identity cards.

During Wednesday's prime minister's question time the Liberal Democrat leader repeatedly quizzed Tony Blair on the issue.

When asked about the cost of the scheme announced in the Queen's Speech, Blair said the cards would cost £80.

He claimed £65 of that figure was due to the biometric technology that was anyway required for new passports and insisted it represented "value for money".

Kennedy responded: "Originally the Home Office said the scheme would cost £3 billion, this week they say it has more than doubled.

"Given the history of this government on introducing complex information technology, not the least with the Child Support Agency and tax credits, will the prime minister rule out any company that had anything to do with those fiascos having anything to do with identity card systems?

"Hasn't this scheme, financially and in terms of the potential complications for the individual citizen, got all the hallmarks of another government fiasco in the making and another case of the individual being left to pick up the tab?"

Responding, Blair stressed the need for biometric passports which would account for most of the cost.

"The reason why believe this measure is necessary is not just because of terrorism but also because of access to services like the NHS," the prime minister added.

"We think it is legitimate and right that, in this day and age, we ask people to have identity cards and that is what we are going to do."

"Sir David Steel got this right when he said 'I don't take the party line on this, I think people will find them very useful'," Blair added.