At his news conference yesterday Gordon Brown was asked how long the bank rescue scheme would remain in place.

"I think your point is what is the temporary nature of this," Brown replied. "As quickly as possible we want to get back to a situation where the bank shares are held in the private sector, and we have no ambition to hold on to shares longer than is necessary."

But a few hours later, when the City minister Lord Myners was making a statement in the Lords about the government's plans, he said that one aspect of the scheme could be in place for almost 10 years. He was talking about the proposal to allow banks to insure themselves against bad debts. In response to a question from Lord Lamont, he said:

The duration of the policy will be important, because we need a policy that will take financial markets through this economic downturn and beyond the next cycle, so we are probably talking about a policy duration of no fewer than five years and probably no longer than eight or nine years.

Myners – who as Paul Myners was chairman of the Guardian Media Group – also gave some indication of the complexity involved in setting up an asset protection scheme for the banks.

Establishing the asset protection scheme will take six to eight weeks. It will involve a huge amount of data analysis. I envisage well over a billion items of individual data reviewed for each bank that approached us in that connection. We will be drawing on the support of external advisers – accountants, actuaries and lawyers.