* Putin to ask Turkey to participate in South Stream project
* Putin to emphasize South Stream supply security
By Thomas Grove
ISTANBUL, Aug 4 (Reuters) - Russia's Prime Minister Vladimir Putin is likely to use a trip to Ankara on Thursday to try to get Turkey to support a mega pipeline that will help Moscow outpace a rival EU project to safeguard its European gas market.
Putin's trip follows a signing ceremony in Ankara last month for transit agreements for the European Union-backed Nabucco natural gas pipeline, designed to counter Russia's strong influence on European energy supplies.
Moscow has separately been gathering support for its own South Stream pipeline project designed to carry 63 billion cubic metres of gas to protect its 25 percent share of the European gas market.
On Thursday Putin is expected to promise South Stream will be built quicker than Nabucco despite last month's political fanfare and will seek to convince EU candidate Turkey to allow Moscow's 10 billion euro project to carry gas from the Russian coast to Europe via Turkey's Black Sea waters.
"These are rival projects, they're not complementary. If one is successful then the other should be postponed for 10 years. They are targeting the same customers, there is not enough resources and the funding is not there," said Necdet Pamir, Turkish Committee member of the World Energy Council.
"And here Russia needs Turkey to let the pipeline pass through its exclusive (territorial waters)," he said.
Turkish rejection of the project would force South Stream to go through the territorial waters of Ukraine, with which Russia has already experienced two gas rows over the past three years.
SECURE SUPPLIES
Nabucco consortium members say their July accord has solved political problems and infighting that has slowed development of the pipeline, but Putin is likely to point out that the 31 bcm Nabucco has yet to secure any gas.
"Nabucco is a project for generations to come, we all know it has no gas at this time; South Stream has all the gas. For Nabucco there are no upstream suppliers right now, it's all lip service, and that is what Putin is likely to press," said independent energy analyst Haluk Direskeneli.
Both projects are looking to Azeri resources.
But despite Azeri statements that Baku has not yet decided what to do with some trillion cubic metres of gas lying under its waters, the head of Gazprom, Russia's state-run gas giant, Alexei Miller said in June that Azerbaijan had promised Russia priority in buying its gas.
Russia is likely to sweeten the pot for Turkey by offering assistance on a number of Ankara-backed energy projects, including the extension of a current Black Sea pipeline, a Turkish oil pipeline and a series of nuclear power plants.
"We are still assessing the offer from Russia on the South Stream," said a senior Turkish government source. "Russia is in an important place to help bring a number of projects to life. The decision could create some important initiatives," he said.
Ankara is looking for Russian oil that would fill up a planned government-backed oil pipeline that is expected to travel from the Black Sea coastal town of Samsun to the Mediterranean oil hub of Ceyhan.
Turkey is also looking to Moscow for cooperation on a controversial 2008 nuclear power tender in which Atomstroiexport and its partners Inter RAO of Russia and Turkey's Park Teknik were the sole bidders.
Turkey has delayed final approval of the tender over pricing offered by the consortium. (Additional reporting by Orhan Coskun in Ankara and Gleb Bryanski in Moscow; editing by James Jukwey)