Italian prosecutors said late Tuesday they are seeking an eight-year prison term against the head of oil company Eni, Claudio Descalzi, as part of a long-running corruption case implicating the Italian firm and its UK counterpart Shell in Nigeria.

The prosecutors are also seeking a 10-year term for Nigeria’s energy minister at the time, Dan Etete, as well as the recovery of the $1.1 billion.

Italian investigators suspect the two oil groups used bribes to obtain rights in 2011 to a Nigerian offshore oil block estimated to hold nine billion barrels of crude, for $1.3 billion (1.1 billion euros).

Out of that sum, almost $1.1 billion was believed to be bribes to a London bank account that ended up going to various Nigerian politicians, including Etete.

The trial of Eni and Shell for corruption opened in the spring of 2018 and two middlemen – a Nigerian and an Italian – were handed four-year prison terms later that year after an accelerated trial.

Both oil companies deny any wrongdoing.

Prosecutors also requested an eight-year prison term for Paolo Scaroni, who was chief executive of Eni at the time, and a seven-year term for Malcolm Brinded who was then Shell’s head of exploration and production.

In a statement, Eni called the requests by prosecutors completely groundless and noted that US authorities closed their probes and the payments had been made following an inquiry by Britain’s Serious Organised Crime Agency.

In 1998, the OPL 245 was awarded by Etete to Malabu Oil and Gas, which later sold it to Eni and Shell.

The deal saw the Nigerian government act as an intermediary between the oil majors and Malabu Oil and Gas, a company allegedly controlled by Etete.

Milan prosecutors alleged that bribes were paid to win the licence to explore the field, which has never entered into production.

AFP.