Russian gas giant Gazprom could become an official sponsor to Bulgarian top football team Levski Sofia, stated Gazprom CEO Alexei Miller.

Thursday Miller is in Sofia, where he signed in the presence of Bulgarian PM Boyko Borisov the final investment agreement for the Bulgarian participation in the South Stream natural gas pipeline project.

As part of the energy visit, Bulgaria and Russia also signed a new 10-year natural gas delivery contract that lowered prices for Bulgaria with 20%.

"If cooperation between Bulgaria and Russia continues to go so well, we can consider financing the Levski football team," said Miller.

Over the summer, Bulgarian PM Borisov had said that Gazprom is considering financing Levski's arch-rival, financially troubled CSKA Sofia.

At the press conference Thursday, it was not made clear why Gazprom preferred Levski over CSKA.

Speculations have it that Gazprom prefers sponsoring teams playing in blue jerseys, corresponding to the company's own colors, and natural gas as "the blue fuel."

Bulgarian team Levski plays in blue, while CSKA plays in red.

The most famous football teams sponsored by Gazprom are German Schalke 04 and Russian Zenit.