Following the rescue in November 2015 of Banca Etruria, Banca Marche, CariChieti and CariFerrara, Italy has struggled to find a buyer for them. It rejected bids from private equity funds over the summer as too low.

UBI has expressed an interest in buying three of the lenders, but set conditions including the offloading of 2.2 billion euros (£1.9 billion) in bad debts which banking industry bailout fund Atlante is set to acquire.

The sale to UBI was expected to be finalised by the end of 2016. But sources said last week the deal had been delayed because the EU Commission had told Italy's resolution fund, which owns the banks, to ask the rejected bidders if they were still interested.

One of the sources said a dozen letters sent out to investors to invite fresh bids had remained unanswered.

"Over the next few days the deal will be wrapped up," a second source said.

(Reporting by Andrea Mandala Writing by Valentina Za; Editing by Ruth Pitchford)