The sweetened £1.5bn offer, due to be tabled tomorrow, will propose Lloyds demerge the 632 "Project Verde" branches, float the business and allow NBNK to fully underwrite the demerger in cash. Lloyds has always said if the deal with Co-op did not go through, "Plan B" would be to float the business.
That would mean shareholders in Lloyds – including the taxpayer, which owns 40pc of Lloyds through UK Financial Investments – will be allowed to choose between taking a new share in the Verde spin-off or accepting cash from NBNK.
The offer could provide Lloyds with an alternative to the proposed £1.4bn sale to the Co-op, which is the subject of regulatory delay amid questions from the Financial Services Authority over corporate governance and the structure of the mutual.
It would allow Lloyds to float the business at the same time as providing a safety net amid concerns investors would not have a strong appetite for what would amount to a mini-Lloyds. A number of fund managers spoken to by The Sunday Telegraph have expressed concern over the merits of buying into a float of the Verde business.
"Do they think we are mugs?" asked one fund manager. "If Lloyds can't sell [to the Co-op] why do they think we should pick up the tab?" Another large investor said it was a difficult proposition to know why to buy a "second smaller Lloyds".
Lloyds is being forced to sell the Verde branches as the result of a European Commission competition ruling. They must complete the sale by November 2013.
NBNK is to spend the next two months attempting to revive talks with Lloyds, after which time it will assess how to move forward if progress fails to materialise. The NBNK banking shell, whose investors include Blackrock, Invesco, Moore Capital, Aviva and F&C, is understood to have already received interest from Virgin Money and Metro Bank over the possibility of a reverse takeover of NBNK's quoted vehicle.
This would give Virgin or Metro – both planning to float on the UK stock market in the next two years – an unusual opportunity to piggy back on NBNK's strong shareholder register as well as access its quoted position on the London Stock Exchange's AIM market.
News of NBNK's intentions comes as new concerns are raised by the Financial Services Authority over the state of the Co-op's bid. Last December Lloyds chose to enter exclusive talks with the Co-op rather than NBNK.
It is understood that significant question marks remain about the Co-op's complex corporate structure, which involves a group board and a number of subsidiary boards.
In addition, The Sunday Telegraph understands the FSA is questioning the lack of a permanent chief executive for the bank following the departure of Neville Richardson.
The FSA is also looking into the mutual's ability to finance the acquisition, and whether it would have enough capital were there another financial crisis. The Co-op, with the help of bankers Barclays Capital and Credit Suisse, is understood to be considering a number of funding options in addition to debt financing. These are believed to include potential disposals of non-core assets, temporary borrowing and a members bond.
Last Thursday, Lloyds said it remained committed to the Co-op and hoped to be in a position to sign a deal by the end of June, rather than the end of March as first thought. Insiders at the Co-op, however, question why the March deadline was given, saying regulatory approval was always going to be a long process.