Lloyds Banking Group has put a 20% stake in wealth manager St James's Place (SJP) up for sale.
The bank signalled its intention to sell 102 million of its shares "to simplify the group and focus on its core customer franchise".
Lloyds said institutional shareholders will be sought for the placing by BofA Merrill Lynch (BofAML) through an accelerated bookbuild.
The price at which the shares are to be placed will be agreed by Lloyds and BofAML at the close of the bookbuilding process.
Assuming Lloyds sells the full amount, it will then hold around 37% of the advisory firm. It will hold this position for at least a year.
It will also no longer consolidate SJP's results in its accounts, which this year accounted for profits of £76m. Selling 20% will raise between £350m and £400m for the bank.
The announcement will lead to further speculation that Lloyds is attempting to exit its relationship with SJP entirely if a buyer can be sought.
In November, the Sunday Times reported the taxpayer-backed bank was planning to offload its entire holding, raising around £1bn.
SJP's chief executive, David Bellamy (pictured), and the rest of the management team will remain in place despite the sale, Lloyds added.
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