The Financial Services Authority, which is closely observing the negotiations with government, is thought to be concerned by whether the cash will be enough to prevent the lenders from collapsing. The concerns follow package negotiations over the weekend, ahead of plans today to shell out £40bn in cash from taxpayers' coffers into Britain's struggling high street lenders. Initial plans to lend the banks £25bn immediately and a £25bn later are set to increase to £75bn as HBOS and RBS could alone use £25bn each. The banks in which government is set to hold major stakes include the Royal Bank of Scotland and HBOS while it will take smaller stakes in Lloyds TSB and Barclays. Government's package may include £200bn for interbank lending with a further £250bn guarantee of bank debt, the Guardian reported. But a government source said: 'This is not nationalisation. This is the banks coming to us requesting capital. 'If we are going to take a significant share of these banks, we have got to protect the interests of the taxpayer. But we have no intention of taking a long-term stake. We will sell once we have returned to normality.'