Bloomberg reports that RBS is said to be narrowing the field for bidders for 300-plus branches.

Royal Bank of Scotland Group has begun to go through bidders for the 316 branches that regulators are forcing it to sell as UK fund managers face off against offers from US private equity firms, Bloomberg news agency reported unnamed people with knowledge of the discussions as saying.

The news agency claimed that a group of 20 UK institutions - including Schroders Plc and F&C Asset Management Plc - were expected to submit a bid before tonight's deadline, citing two unnamed people, who it said had asked not to be identified as the talks were private.

Again citing unnamed individuals, the news agency further reported that JC Flowers & Co., would make an offer with Apollo Global Management LLC, adding that Centerbridge Partners could team up with Corsair Capital.

Bloomberg said the people said that AnaCap Financial Partners LLP would make a separate offer and added that one person had said that Virgin Money Holdings (U.K.) might also bid.

RBS has to sell the outlets by 2014 to comply with European Union state-aid rules after receiving £45.5bn in a bank bailout in 2008 and 2009.

Bloomberg reported that officials at RBS, Centerbridge, AnaCap, Corsair, Virgin, JC Flowers and Apollo declined to comment. Officials at F&C and Schroders didn't immediately respond to requests for comment.