Prime Minister Vladimir Putin on Wednesday said Russia had won Turkey's backing for Moscow to build a key section of a new gas pipeline seen as a rival of an EU-backed project in Turkish waters.
Putin's comments came after talks with his Turkish counterpart Recep Tayyip Erdogan that were the latest example of the expanding strategic relationship between Moscow and Ankara.
"We have agreed that by November 10 the Turkish government will carry out an audit and will give us the permission for the construction" of the South Stream pipeline, Putin said.
Russia wants to build a section of the South Stream pipeline through Turkey's portion of the Black Sea to create a new route for Russian gas to Europe that will by-pass Ukraine.
But Turkey is also a key player in the rival EU-backed Nabucco pipeline which aims to carry gas from the Caspian Sea region to Europe and is seen as a way of reducing European reliance on Russian gas.
Turkey in August agreed to allow Moscow to start surveys in its territorial waters in the Black Sea for South Stream.
Putin said the ecological surveys had already been completed while the seismological and geological surveys were 85-90 percent complete.
It was unclear whether gas supplies were sufficient to fill two pipelines and Moscow has been keen to complete South Stream ahead of its rival, with plans to go online with the pipeline's section in Turkish waters as early as 2013.
South Stream is being jointly developed by Russian gas giant Gazprom and Italy's Eni.
Turkey in turn is seeking Russian support for a planned Turkish oil pipeline to be built from the Black Sea port of Samsun to Ceyhan on the Mediterranean.
Russia will play an active role in the project and the two sides are in talks over Moscow taking a stake, Russian deputy Prime Minister Igor Sechin told reporters on the sidelines of the meetings.
Putin said he had floated the signing of a tripartite agreement between Italy, Russia and Turkey on the pipeline and added that Erdogan had agreed.
The two countries have also joined efforts to broker peace between ex-Soviet states Azerbaijan and Armenia, which are still technically at war over the mountainous Nagorno-Karabakh region.
Shared concerns over stability in the Caucasus were tested as Russia fought a brief war with Georgia in August 2008, but Moscow has since played a role in the recent rapprochement between Turkey and its ally Armenia.
Russia is Turkey's main gas supplier, accounting for about 60 percent of the country's gas imports.
AFP has contributed to the report.