Britain is to start selling off its shares in the Royal Bank of Scotland by disposing of 5.2 percent of the state-rescued institution, the Treasury announced Monday.

RBS was bailed out with public money at a cost of £45.5 billion ($70.9 billion, 64.7 billion euros) following the 2008 global financial crisis and the British government holds 78.3 percent of the bank's shares.

The Treasury owns its stake in RBS through UK Financial Investments and finance minister George Osborne, the chancellor of the Exchequer, agreed with the limited company's desire to start the sell-off, officials said.

The government paid about £5 a share for the bank, compared with the current price of about £3.39.

"UKFI today advised the chancellor it would be appropriate to conduct the first sale of the government's shareholding in RBS," a Treasury spokesman said.

"The chancellor agrees with that advice and has authorised the process to begin."

He said the government's objectives for its shares in bailed-out banks were "getting the best value for the taxpayer, maximising support for the economy and restoring them to private ownership".

"The government will only conclude a sale if these objectives are met," he added.

UKFI plans to sell about three-quarters of its holding in RBS within the next five years.

UKFI estimates that the RBS share price will rise as the bank returns to health and more stock is sold to the market.

It said it would sell around 600 million shares, with UKFI's holding reducing from approximately 78.3 percent to approximately 73.2 percent.

Details of the number of shares and the placing price will be announced "in due course", it said.

RBS declined to comment on the government's plans.