The Nabucco pipeline company announced it was ready to start land acquisition studies in more than 20 provinces in Turkey.
"Nabucco Gas Pipeline International will commence activities pursuant to the 'decision of public utilities' concerning the pipeline route within the boundaries of Turkey," the company said in a statement.
The company described this as "a very important step" in the project that is seen as a prerequisite to start land acquisition activities in Turkish territory.
Europe is looking for ways to break the Russian grip on the natural gas sector by pursuing a series of pipelines for the so-called Southern Corridor. Of those, Nabucco is the most ambitious though its $10 billion price tag and lack of firm supplier commitments is causing critics to emerge.
Turkish officials had said Nabucco was important because European demands for natural gas won't be met even if all projects in the Southern Corridor eventually come on stream.
The pipeline would link the eastern Turkish border to Austria via Bulgaria, Romania and Hungary.