Chancellor Philip Hammond said the process would result in the taxpayer recovering all of the £20 billion poured into the bank to save it from collapse during the 2008-09 financial crash.
The treasury has also raised £17bn in tranches of shares sold over recent months.
“We need to recover the taxpayers’ money,” Mr Hammond said, adding that it was not currently practical to offload the government’s stake in the Royal Bank of Scotland while the bank remains subject to fines from the Department of Justice in America and was struggling to sell its Williams & Glyn branch network.