Saudi Telecom Company (STC) and Iliad Group have emerged as the two frontrunners in the bid for Altice's Portuguese business.
As reported by Bloomberg, STC and French telecom billionaire Xavier Niel have made progress during the bidding process.
Warburg, which teamed up with former Credit Suisse chair António Horta-Osório in its bid, has also been invited back for the second round of bidding, according to Bloomberg.
Apollo Global Management and CVC Capital Partners had shown an interest, but are reportedly no longer in the running.
Altice, which is owned by French-Israeli billionaire Patrick Drahi, is looking to ease its debt, which sits at $60 billion.
The company is open to selling its telecoms business and has recently spun off its French data center assets, forming a new company with more than 250 facilities in France, which was then sold to Morgan Stanley.
The Portuguese unit of Atlice has also been separately looking to sell off its data center unit.
Altice Portugal has been grappling with a corruption probe, which led to the arrest of Drahi's fellow co-founder and former chief operating officer Armando Pereira. Drahi told investors in August that he felt "betrayed."
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