Decisions related to natural gas transit infrastructure tied to Russian supplies are in the hands of the Turkish government, a Gazprom chairman said.

Russian and Turkish officials discussed prospects for the so-called Turkish Stream natural gas pipeline system. Alexander Medvedev, a deputy chairman at Russian energy company Gazprom, said it's up to the Turkish government to take the next steps on the pipeline.

"We have already stated that the ball is in Turkey's court," he was quoted by Russian news agency Sputnik as saying.

Russian energy company Gazprom proposed the so-called Turkish Stream gas pipeline as an alternative to a broader South Stream pipeline network meant to feed European markets. Turkish Stream was suspended amid simmering acrimony between the two countries.

Political ties between Russia and Turkey have soured in recent years, though both sides had reviewed the potential for energy cooperation last year. Russian military intervention in Syria frustrated the Turkish government and its allies in the NATO alliance and last year's downing of a Russian military jet in Turkish airspace was met with measured anger by the Kremlin.

Turkey is a key energy hub given its geographic position between Europe, Central Asia and the Middle East. The Turkish government in early July shut down the Bosphorus Strait briefly after a coup attempt. Last week, the Russian government said it would revisit the Burgas-Alexandroupolis oil pipeline if security concerns lingered.

Bulgaria signed an agreement in 2007 with Russia and Greece to build the 174-mile pipeline to bypass crowded waterways near Turkey by crossing an overland route to the Aegean Sea, though Sofia backed out in 2011 because of financial concerns.