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ROME, Feb 21 (Reuters) - Atlantia's shareholders on Wednesday approved superficial changes to its offer for Spanish toll-road operator Abertis and left scope for the board to sweeten the bid in the coming weeks.
The Italian motorway and airport operator is competing against Hochtief, the German arm of Spanish builder ACS, in the race to buy Abertis.
The tussle effectively pits the Benetton family, which controls Atlantia, against Spanish businessman and Real Madrid president Florentino Perez, the leading investor in ACS.
Hochtief is currently in the lead, with an offer valuing Abertis at around 16.7 billion euros ($20.6 billion). This valuation includes Hochtief's proposal to trim its bid by 0.40 euro/share if Abertis approves a dividend payout in March.
Atlantia's shareholders on Wedneaday gave a green light to extending to Nov. 30 a deadline for the launch of a cash call linked to the Abertis offer.
They also decided to shorten to 90 days a lock-up period during which Abertis shareholders would not be able to sell new Atlantia shares they are set to receive as part of the bid.
Atlantia CEO Giovanni Castellucci kept his cards close to his chest on Wednesday.
However, he said Abertis' current share price of around 19 euros and Atlantia's offer of 16.50 euros a share were not that far apart if one considered possible future synergies.
Atlantia's cash-and-share bid is valuing the Spanish company at around 15.3 billion euros. One source told Reuters the Italian group was counting on at least 2.5 billion euros in expected cost savings to raise its offer.
"The value you offer for a target company normally does not include synergies, while the market considers that bidders are willing to pay a premium related to synergies and this is what is included in the market price," Castellucci said.
He did not elaborate and repeated the group would decide whether to modify the terms of its offer only once Hochtief's bid got a regulatory green light.
A verdict by the Spanish market watchdog CNMV is expected in the coming days, sources said.
Once the CNMV has cleared the German offer, Hochtief and Atlantia's bids will run in parallel for one month with the possibility for both groups to improve their proposals.
Atlantia is expected to up the price of its offer and open the door to accept all cash in return for Abertis' shares, sources have said, adding the Italian group will wait until the last moment to put forward an improved proposal. ($1 = 0.8121 euros) (Editing by Keith Weir)