Exxon Mobil's (XOM) Esso and Eni (E) are among the six oil companies that were fined a combined 936.7 million euros ($1.09 billion) for allegedly establishing a fuel price "cartel," the Italian Competition Authority said Friday.

An investigation showed that Esso, Eni, Ip, Q8, Saras and Tamoil coordinated to set the value of the bio component factored into fuel prices, with values rising to about 60 euros per cubic meter in 2023 from 20 euros in 2019, the Italian competition watchdog said.

The authority imposed a fine of 336.2 million euros on Eni and 129.4 million euros on Esso, among others.

Eni said that it disagrees with the Italian Competition Authority's findings and that it will defend its case and reputation.

"In addition to the damage resulting from an unfair fine, which is of a huge amount, today's measure also constitutes yet another serious damage to Eni's reputation, as it is being linked to collusive practices to which the company is completely unrelated," Eni said.

Exxon, Q8, IP, Tamoil, and Saras didn't immediately respond to MT Newswires' requests for comment.