LONDON/PARIS (Reuters) - Rival consortia led by U.S. buyout fund KKR KKR.N and Germany's insurer Allianz ALVG.DE are among the four main contenders for a stake in the fiber network business of Dutch-based telecom company Altice ATCA.AS, sources said.

FILE PHOTO - An advertising board is seen during the first demonstration of the technology 5G in Lisbon, Portugal June 4, 2018. REUTERS/Rafael Marchante

The two other bidding groups are led by Australian investment firm Macquarie MQG.AX and U.S. infrastructure fund I Squared Capital respectively, four sources close to the deal told Reuters.

Altice’s majority owner Patrick Drahi is trying to pay down Altice Europe’s 32 billion-euro debt pile and share the burden of ploughing cash into the costly roll-out of its fiber optic network in France.

Altice, which runs France’s second biggest telecom operator SFR, is selling a stake of between 40 and 60 percent in its fiber network business, a deal that could be worth up to 3.6 billion euros ($4.11 billion), the sources said.

The sale has also drawn interest from a number of long-term investors.

Canadian pension fund manager OMERS has teamed up with Allianz while Singapore’s sovereign wealth fund GIC has joined forces with I Squared Capital, one of the sources said.

Altice and Allianz declined to comment. KKR, Macquarie, I Squared Capital, GIC and OMERS were not immediately available for comment.

Altice has asked bidders to submit their final proposals in late November but the deadline could be further extended, the sources said. The sources said the winner will not be selected until mid or late December.

The business may raise anything between 1.8 and 3.6 billion euros but the price will largely depend on the final terms of the agreement between Altice Europe’s infrastructure business and its telecom carrier, the sources said.

Altice wants to share the same degree of governance control with the investors and have a say on key decisions, they said.

In June, the Dutch-based group raised 2.5 billion euros in by selling stakes in its telecoms towers businesses in France and Portugal.

KKR won the auction for the French towers and formed a new company called SFR TowerCo, comprising 10,198 sites operated by Altice’s French subsidiary SFR.

In Portugal, Morgan Stanley Infrastructure Partners and Horizon Equity Partners bought 75 percent of a newly-formed domestic towers business.

Altice remains in restructuring mode with Drahi fighting to revive its fortunes after growing rapidly in recent years through a series of acquisitions.

A sudden loss of investors’ confidence in Drahi’s commercial results in France caused a steep fall in the stock about 10 months ago, triggering the departure of the chief executive, a strategic turnaround plan and the separation of Altice’s European and U.S. divisions.

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