Deputy Prime Minister Nick Clegg has called for the public to be given shares in both Lloyds and RBS.
Clegg says the Government should give voters the benefit of any long-term gains made when shares in the part-nationalised banks are sold.
The taxpayer owns 83 per cent of RBS and 41 per cent of Lloyds after the Government invested £65.8bn at the height of the banking crisis in 2008.
Clegg has written to Chancellor George Osborne to offer his support for the proposal.
Speaking on a trip to Brazil, Clegg said it was important to remember it was taxpayers’ money used to keep the banking system afloat.
He said: “I think, in a sense, as a society we are condemned to take an interest in our banking system.”
He added: “You are giving the Treasury an assurance that they will break even but you are not giving the Treasury the freedom to grab the windfall if there is one.”
The 45 million people on the electoral roll would be given free shares in the bailed-out banks as part of the plan.
The plan was first suggested in March with a host of Liberal Democrat MPs backing a proposal developed by City firm Portman Capital.
Clegg admitted a huge amount of detail needed to be worked on to make the plan work.