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By Sergio Goncalves and Leila Abboud
LISBON/PARIS, Oct 9 (Reuters) - Altice, a holding company backed by billionaire cable entrepreneur Patrick Drahi, wants to enter into exclusive talks with Brazil's Oi to buy its Portuguese telecoms operation, sources familiar with the situation said on Thursday.
Altice believes it can move quickly toward a deal, which is likely to value the Portugal business at between 6 billion euros ($7.6 billion) and 6.5 billion, according to the sources.
A deal would build on a recent acquisition spree by Altice, whose Numericable unit in April clinched the multi-billion euro purchase of France's second-largest mobile operator SFR from Vivendi SA.
The sale would also mark the effective unwinding of Oi's purchase of Portugal Telecom, unveiled in December 2013, that was supposed to create a stronger company with a strengthened balance sheet.
Instead, the merger has been rocked by fallout from a banking scandal in Portugal that weakened Portugal Telecom, leaving the combined company deep in debt and struggling in a consolidating Brazilian market.
Oi Chief Executive Zeinal Bava resigned on Tuesday, a day after the company disclosed it was studying asset disposals, such as its stake in Africatel Holdings BV, to pay down its debt.
Oi has yet to make a decision on a disposal of its Portuguese assets and hasn't received any proposal for them, it said on Monday.
Altice and Oi have been in "high-level" talks in recent weeks and have already discussed issues including price and proposed deal structures, as well as exchanged information on the business.
But there is complexity in the governance structure of Oi and Altice is so far only talking to Brazilian and Portuguese shareholders of the group, not to the management board, one of the sources said.
Oi is Brazil's biggest fixed-line phone provider but trails competitors Telefonica, Telecom Italia -owned Tim Brasil, and America Movil in mobile.
Altice, which owns telecoms in Israel and the Dominican Republic, as well as French cable operator Numericable, is on the hunt for acquisitions, particularly in countries where it is already present.
Altice already owns two small cable companies Cabovisao and Oni in Portugal, which had 230,000 customers at the end of the second quarter.
Numericable agreed to buy SFR in April from Vivendi after offering 13.5 billion euros in cash, a milestone payment of 750 million euros linked to underlying return on capital expenditure and a 20 percent stake in the new entity.
1 US dollar = 0.7885 euro Writing by Axel Bugge; Editing by David Holmes