ST. PETERSBURG - Deals with an estimated total worth of about 9.6 trillion rubles (about $300 billion?dollars) have been signed during an economic forum held in the Russian city of St. Petersburg, the Russian authorities said on Saturday.

More than 100 investment deals and letters of intent have been inked during the three-day St. Petersburg International Economic Forum (SPIEF) starting on Thursday, Russian Deputy Economic Development Minister Sergei Belyakov told reporters here.

Among them is a 25-year deal between China National Petroleum Corporation (CNPC) and Russian oil giant Rosneft, which alone has an estimated value of 270 billion dollars.

Other major contracts include an agreement on liquefied natural gas (LNG) deliveries via the South Stream pipeline between Rosneft and Electricity of France.

CNPC has also struck a deal with Russian LNG operator Novatek on the acquisition of a 20-percent stake of the Yamal LNG project.

SPIEF, which has been held annually since 1997, attracted this year more than 5,000 finance specialists, banking industry representatives and senior government officials from more than 70 countries.