The British government plans to sell a STG3 billion ($A5.48 billion) chunk of its stake in part-nationalised Lloyds Banking Group, which was bailed out by taxpayers during the 2008 financial crisis.
The Treasury says it is introducing a trading plan in which shares will be sold on the market "in an orderly and measured way."
It says sales could begin within days and the plan, overseen by Morgan Stanley, will continue for about six months.
Shares won't be sold below the average price which the previous government paid for them, 73.6 pence.
The new sale aims to shed about a fifth of the government's remaining 25 per cent stake in the bank.
Lloyds shares closed 1.5 per cent lower at 75.35 pence Wednesday on the London Stock Exchange.