Standard & Poor's only expected Gazprom to claim $1.2 billion from Ukraine's Naftogaz for not buying the agreed volume of gas in 2012, not the $7 billion that the Russian gas giant is actually demanding.

S&P said in an analytical report dated January 23 that it based its calculation on the fact that Naftogaz bought 2.8 billion cubic meters less gas and than contracts stated and the gas price was $424 per thousand cubic meters.

The agency said it thought Gazprom could claim more than $5 billion from the Ukrainian company in 2013.

S&P estimates Gazprom supplied Ukraine with 30 bcm of gas last year. It said Naftogaz was obliged to import at least 32.8 bcm under the take-or-pay arrangement in 2012 and 2013.

Ukraine cut gas imports 26.5% in 2012 to 32.939 bcm. Naftogaz and Dmytro Firtash's OstChem Holding Limited bought nearly all of this gas from Russia. Naftogaz bought another 55 million cu m from Germany's RWE in November-December.

Naftogaz Ukrainy has confirmed reports that it has received a $7 billion claim from Gazprom for gas Ukraine failed to import last year under its 2009 contract terms. The company said it had paid all bills received from Gazprom ahead of deadlines and in full and had repeatedly warned the Russian company that it planned to reduce its purchases of gas in 2012.