MOSCOW, Jan. 3 (Xinhuanet) -- Russian gas giant Gazprom vowed on Tuesday to stick to its demand to more than quadruple the price of gas for Ukraine in new talks later in the day to resolve a grueling dispute that has led to a cutoff of Russian gas supply to Ukraine.

   A delegation of Ukraine's national oil and gas company Naftogaz Ukrainy arrived earlier in the Russian capital for new talks with Gazprom.

   Gazprom is willing to reach an agreement with Ukraine on gas deliveries but will not make any more concessions, Gazprom spokesman Sergei Kupriyanov said on the Echo of Moscow radio.

   "We have a real opportunity for reaching agreement with Ukraine on a bilateral basis," he said.

   Ukraine was buying Russian gas at 50 U.S. dollars per 1,000 cubic meters over the past year, but Gazprom has asked Ukraine to pay 230 dollars, saying the price hike was needed to conform to world gas price levels.

   "We realize that Ukraine is living through a difficult period. It can only switch to the market-based relations gradually, but when a very lucrative proposal was sent to Ukraine on Dec. 31, the answer was 'No,'" Kupriyanov said.

   Gazprom has said Ukraine turned down an offer late Saturday by President Vladimir Putin, who approved a three-month freeze on the gas price if Ukraine accepted a price hike starting in the second quarter.

   Kupriyanov said an international audit company Gazprom invited confirmed Ukraine's unsanctioned tapping of gas intended for European clients since a cutback of gas supply to Ukraine on Sunday but Gazprom would refrain from making the records public for the time being.

   About 80 percent of the gas the European Union buys from Gazprom is sent through pipelines that cross Ukraine.

   Earlier, the spokesman said Ukraine illegally tapped 104.8 million cubic meters of Russian export gas on Sunday and 118.7 million cubic meters on Monday. Enditem