"We signed today the final (in a series of agreements) with allthe necessary European partners for us to be able to complete this project," Putin said after talks with his Slovenian counterpart Borut Pahor at his residence outside Moscow.
Earlier in the day, Energy Minister Sergei Shmatko and Slovenian Economy Minister Matej Lahovnik signed an agreement on the passage of the South Stream gas pipeline across Slovenian territory.
The South Stream gas pipeline, scheduled to be finished by 2015,is part of Russian efforts to reduce reliance on transit nations. It is a rival project to the European Union-backed Nabucco.
The pipeline will run through several European countries as well as through the Black and Adriatic seas, bypassing Ukraine, which has frequent disputes with Russia over gas supplies and transits.
The massive project aims to annually pump 31 billion cubic meters of Central Asian and Russian gas to the Balkans and on to other European countries. The pipeline's capacity was expected to be eventually raised to 63 billion cubic meters.