Mexican state-run oil company Pemex has hired Credit Agricole to sell its stake of just over 9 % in Spanish oil major Repsol, according to Reuters.

Pemex, a long-time Repsol shareholder, has had an increasingly fractious relationship with the Spanish group.

It has publicly locked horns with Repsol chairman Antonio Brufau over how he handled negotiations after Argentina’s 2012 seizure of the company’s YPF business, which ended in a US$5bil settlement this year.

Pemex could sell its Repsol holding in several stages, including a market offering. Pemex has 9.3% of the Spanish group, according to a Repsol filing witho Madrid’s stock market regulator yesterday.

The stake’s market value is worth about 2.3 billion euros (US$3.19bil) the third largest stakeholder in Repsol

Separately, Spanish newspaper Expansion reported that businessman Juan Miguel Villar Mir, chairman of Spanish infrastructure company OHL, had offered to take a large stake in Repsol if any shareholders sold out.

A spokesman for Grupo Villar Mir, a holding company comprising the businessman’s OHL stake as well as his energy and property ventures, denied the report’s claims.

“There has been no contact or conversation over taking a stake in Repsol,” the spokesman said.

Spanish bank La Caixa is Repsol’s biggest shareholder, with about 12% of the company.

Repsol last week created the new role of chief executive officer after pressure from Pemex to shake up the management structure.