State-owned oil company Petróleo Brasileiro SA started the process of selling its remaining 10% stake in natural gas transportation and storage unit Transportadora Associada de Gás SA, according to a Dec. 11 securities filing.

The Brazilian oil giant, also known as Petrobras, closed a sale of a 90% stake in the unit, commonly known as TAG, in June to a consortium comprised of Engie SA and Canadian investment fund Caisse de dépôt et placement du Québec, which won the bidding process in April with an $8.6 billion proposal.

Reuters previously reported that Engie's Brazilian unit wants to acquire Petrobras remaining 10% stake in TAG. Maurício Bähr, CEO of the Engie Group in Brazil, had said that the company has the right to acquire between 6.5% and 7% of Petrobras' 10% stake. Bähr also told Reuters that an Engie-led TAG investor group plans to start talks to acquire the stake in the first half of 2020, under their contract with Petrobras.

The sale is part of Petrobras' plan to reduce debt by selling assets. The divestment program has brought in $15.3 billion year-to-date as of Oct. 15, with the Brazilian oil major not only planning to extend the program to 2024 but also possibly expanding it to between $20 billion and $30 billion from 2020 to 2024.

TAG currently holds long-term permits to operate and manage a 4,500-kilometer gas pipeline system with an installed capacity of 75 million cubic meters per day, located in Brazil's north and northeast regions.