The creation of the joint venture was a key part of a deal that ended a Russian-Ukrainian dispute over gas prices last month.
The joint venture, UkrGazEnergo, was set up between Ukraine's Naftohaz state energy company and an intermediary company RosUkrEnergo.
The Swiss-registered RosUkrEnergo has been criticized for lack of transparency as it is equally owned by Gazprom, Russia's state-controlled natural gas company and a group of investors whose names have not been made public.
Aleksandr Ryazanov, deputy chairman of Gazprom, was elected to chair the new joint venture's supervisory body.
According to a Naftohaz spokesman, the new joint venture will sell Russian and Central Asian gas to Ukraine at the price of $95 per 1,000 cubic meters over the next five years.
(Ukrayinska pravda, Interfax-Ukraine, ITAR-TASS)