A new round of cooperation negotiations over natural gas between Russia's Gazprom and China's CNPC failed to reach a deal due to conflicts over advance payment, Russian negotiators from Gazprom said Wednesday.

Earlier this month, Gazprom offered to pay $250 per cubic kilometer of natural gas, $100 lower than its previous offering of $350 to $380 per cubic kilometer. However, Gazprom wanted China to prepay $40 billion, in return for a Russian guarantee to supply China for the next 30 years.

One analyst said such prepayment was unprecedented due to the risk in gas investment.