MADRID/MILAN (Reuters) - Spanish builder ACS (ACS.MC) is in talks with various pension and infrastructure funds and private equity firms on a potential counter-bid for Abertis (ABE.MC), two sources familiar with the matter said on Friday.
ACS confirmed it was considering making an offer for Spain's Abertis after Italian infrastructure group Atlantia (ATL.MI), controlled by the Benetton family, bid more than 16 billion euros ($18.6 billion) in May.
Atlantia had offered 16.50 euros per share, looking to create the world's biggest toll road company.
One of the sources also said that the deal, which was not seen as imminent, is likely to involve ACS taking a leading position in Abertis and one or several funds being part of the equity structure.
"Negotiations with funds from Australia and Canada, including sovereign funds, are ongoing, although no agreement has been reached yet," the source said on condition of anonymity.
In its statement to Spain's market regulator on Friday, ACS said it had not yet decided whether to bid for Abertis, which it was studying with external advisers.
Key Capital Partners, Lazard and JP Morgan are the company's advisers on the potential deal, the source said.
ACS and Lazard declined to comment, while representatives of JP Morgan and Key Capital Partners were not immediately available to comment.
Expansion newspaper reported that ACS had been working on its own offer for weeks and could use its German subsidiary Hochtief (HOTG.DE) to launch the counter-bid.
One of the sources said it was too early to say if Hochtief would be part of the deal and there had been no discussions with the German subsidiary.
Analysts said that the most likely scenario now is for Atlantia to improve its offer price because the bid undervalues Abertis. ACS's counter-bid makes strategic sense, they said, because Abertis is a low-risk asset that would complement its own operations.
The market regulator is still looking at whether to approve Atlantia's bid -- a process that usually takes two or three months -- and the Spanish government can block the transaction if it does not fit with Spain's strategic interests.
The Spanish government is following developments very closely, government spokesman Inigo Mendez de Vigo said on Friday.
Atlantia said in a June prospectus that it could consider making a full cash offer for Abertis instead of the initial proposal for a cash-and-shares deal with at least 10 percent of Abertis shareholders taking payment in shares.
News of ACS's possible bid sent its shares down more than 5 percent to the bottom of Spain's blue-chip IBEX index .IBEX. Atlantia shares fell 1.8 percent, while Abertis was up 1.4 percent at 16.70 euros.
A Hochtief spokesman declined to comment on Expansion's report and said it was a matter for ACS, which owns 72 percent of the business. Hochtief shares were down about 6 percent, the biggest faller on Germany's MDAX .MDAXI index of medium-sized companies.
Reporting by Robert Hetz and Jose Elías Rodríguez; Additional reporting by Matthias Inverardi in Frankfurt; Writing by Angus Berwick; Editing by Alexander Smith and David Goodman