Emilio Lozoya, a former chief executive of Mexican oil giant Pemex, is set to face a battery of corruption charges after a Spanish court this week authorised his extradition to his home country.
Lozoya faces allegations of money laundering, bribery and conspiracy relating to contracts awarded to Brazilian construction company Odebrecht in 2012 and the acquisition, by Pemex, of a petrochemicals plant in 2013.
Lozoya, who has denied all charges, fled Mexico in 2019 and was arrested by Spanish police in February.
Several Mexican officials, including President Andres Manuel Lopez Obrador, have already suggested that Lozoya will strike a sentence-reducing co-operation deal with prosecutors once the extradition order is carried out.
A confession by Lozoya could have potential to incriminate high-ranking members of the Institutional Revolutionary Party (PRI), possibly including ex-president Enrique Pena Nieto, who governed Mexico from 2012 to 2018.
Lozoya was a confidant and aide to Pena Nieto, and the connection between the two men includes a role for Lozoya as one of the managers behind the successful 2012 election campaign.
Spanish court papers suggested that Lozoya sought and obtained $4 million in campaign funding from Odebrecht, although they further allege that he may have embezzled part of this sum to allow his wife to buy a property for $1.9 million in the coastal state of Guerrero, Mexico.
The court documents referred to additional allegations that Odebrecht paid Lozoya another $5 million in bribes in order to win a contract for a refinery upgrade.
Another charge relates to the $475 million acquisition of the Agronitrogenados fertiliser plant from Mexican steelmaker AHMSA, which allegedly resulted in a $3.4 million kickback for Lozoya.
Analysts believe the case may benefit Lopez Obrador, who was elected on an anti-corruption and anti-elite ticket but has so far struggled to deliver any significant results on this front, or in the battle to revive Mexico's economy.