Spokesman Borek Konecny added it was too early to say whether Unipetrol — controlled by Poland’s PKN Orlen — would exercise its option of first refusal to buy Eni’s nearly 33 percent stake in the refinery.

“We were informed last week by Eni (that it is negotiating with Gazprom),” Konecny said.

A spokesman for Gazprom, which has forged strong ties with the Italian company for joint operations in Russia and elsewhere, said the gas giant has not yet made a decision. A spokesman for Eni could not immediately be reached.

“Within the framework of strategic partnership agreement signed in 2006, Gazprom is reviewing offers coming from Eni about acquiring the Italian company’s assets in third countries,” a Gazprom spokesman said.

Any sale to Gazprom would likely raise concern in the Czech Republic. Ceska Rafinerska operates a refinery at Litvinov and a second, smaller one in Kralupy.

In 2009, Czech state-run pipeline operator MERO raised the possibility of buying Royal Dutch Shell’s some 16 percent stake in Ceska Rafinerska to keep the refiner out of Russian hands.

Any potential Gazprom sale comes after Unipetrol and the two other shareholders failed to agreed on executive changes at a recent meeting in January — underlining potential strains in the partnership.