The deal would involve Royal Bank of Scotland , Singapore's state investment agency Temasek Holdings, Swiss investment bank UBS and the Asian Development Bank, Caijing magazine said in its cover story seen on Monday.
Roayl Bank of Scotland and Temasek would each acquire 9.9 percent stakes in Bank of China while UBS and the ADB would jointly hold 5 percent, it said, citing an unidentified source familiar with the deal.
A deal would be a major milestone for the bank, China's largest foreign exchange lender, which has been trying to attract strategic foreign investors as it overhauls operations and prepares for a multi-billion dollar stock listing this year.
Last week a source familiar with the talks told Reuters that Royal Bank of Scotland was discussing taking a possible $2.5 billion stake in Bank of China.
On Thursday, Royal Bank of Scotland Chief Executive Fred Goodwin moved to soothe investor concerns that the bank was entering an opaque market in which it is relatively inexperienced, saying it was "looking rather than leaping".