Workers smoke cigarettes outside of a JPMorgan Chase office on May 14, 2012 in New York City. Photo: CFP

JPMorgan has been picked as an adviser for the sale of a stake in a $7.3 billion motorway in Turkey, four sources familiar with the matter said.

Billed as a landmark project in the financing of infrastructure schemes involving the government and the private sector in Turkey, the final section of the 426 kilometer-long Gebze-Orhangazi-Izmir motorway was inaugurated last year to link Istanbul in the northwest to the western port city of Izmir.

Construction consortium Otoyol AS said in late January last year that it had started seeking international advisers to value the project ahead of a possible stake sale.

One of the sources, who had direct knowledge of the matter, said the total value of the sale depended on interest from potential buyers.

JPMorgan declined to comment, while Otoyol did not immediately respond to a request for comment.

Italian contractor Astaldi, which has a stake of just under 19 percent in the project, has been hard hit by a downturn in Italy's construction industry and is under a creditor protection scheme.

It has already agreed to sell its 33 percent stake in the third Bosphorus Bridge to its Turkish partner, a move aimed to help the Italian builder complete a rescue plan.

Turkish firms Nurol Insaat, Özaltin and Makyol each hold a 26.98 percent stake in the consortium while Göçay, another Turkish company, has a 0.2 percent share in the consortium, according to their filings.

The joint venture was awarded a 22-year and four month build, operate, transfer contract in 2009, a model used to finance large-scale infrastructure schemes where the government grants a concession to private firms to finance, build and operate a project.

The total investment in the project was $7.3 billion, including $5 billion from debt, $1.5 billion from equity and $800 million from operational revenues, according to the consortium's website.