* BNP, Credit Suisse, UniCredit, Intesa working on loan-sources
* Atlantia's bid for Abertis seen in coming days, possibly Friday (Adds detail)
By Paola Arosio and Stephen Jewkes
MILAN, May 10 (Reuters) - Four banks are putting together a bridge loan of around 11 billion euros ($12 billion) for Atlantia's potential takeover bid for Spanish rival Abertis, a deal that would create Europe's biggest toll road operator.
Three sources close to the situation said the banks were BNP Paribas, Credit Suisse, UniCredit and Intesa Sanpaolo. The sources said other banks were likely to be involved at a later stage as the consortium is expected to syndicate the loan.
Atlantia, controlled by the Benetton family, is expected to announce its cash-and-share bid for Abertis within days, possibly as early as Friday when its board meets to approve first-quarter results, sources have said.
The deal would create a group with a total turnover of 11.5 billion euros, overtaking the motorway and airports business of France's Vinci, currently Europe's top player. The new group would also have a combined market value of more than 36 billion euros.
Sources told Reuters on Tuesday the two companies were still discussing the terms of the deal after Atlantia approached Abertis with a 16 euro-a-share bid while Abertis's main shareholder, bank La Caixa, had asked for 17 euros per share.
Both Atlantia and Abertis, which have acknowledged they are in talks, have declined to comment on the details of a tie-up.
The deal is expected to see the Benettons reducing their stake in the combined group to around 24 percent from a current 30 percent holding in Atlantia, while La Caixa would end up with around 10 percent from 22.3 percent in Abertis, other sources familiar with the deal said.
Atlantia is keen to diversify away from low-growth Italy, where it now makes 75 percent of its core profits.
A tie-up with Abertis, which gets a third of its core earnings from France and has extensive operations in Latin America, would allow the Italian group to generate around 60 percent of core earnings outside its home market, well ahead of a self-imposed 2020 deadline.
Abertis, in turn, faces the expiration of a series of concessions at home and has seen industrial partner OHL exit completely from its capital in January.
The two companies had already come close to a merger in 2006 but opposition from the Italian government blocked the deal. This time the Rome government is expected to give its blessing to a tie-up in which an Italian company would take control of a foreign rival. (Additional reporting by Stefano Bernabei in Rome, Robert Hetz and Carlos Ruano Navarro in Madrid; Writing by Francesca Landini; Editing by Jane Merriman)