Azerbaijan is weighing proposals for resources from its Shah Deniz 2 gas field from pipeline consortiums involved in the so-called Southern Corridor of transit networks.
Of those, the Nabucco pipeline would be the most ambitious as it would stretch from the eastern border of Turkey to the northern border of Austria to deliver non-Russia gas supplies to European consumers.
Reinhard Mitschek, director of the Nabucco pipeline consortium, told Bloomberg News the price tag "won't be far away" from the existing $11 billion estimate.
Critics of Nabucco say the project is overly ambitious and lacks formal gas agreements to go forward.
Azerbaijan and Turkey reached a natural gas deal this week. A report on the deal from the Platts news service, however, suggested Baku was interested in using existing pipelines to get gas through Turkey from the Shah Deniz field.
Groups managing the Nabucco, the Interconnector Turkey-Greece and the Trans Adriatic Pipeline projects have submitted proposals to Azerbaijan in early October. Mitschek said he expected to sign gas deals as early as November.