Both parties have identified a list of such assets, including power plants in various countries of western and central Europe, as well underground gas storage facilities.

Gazprom said that the listed assets are under evaluation and, in case of value imbalance, E.ON will be required to provide additional assets subject to approval.

The parties were expected to finalize the agreement before the official commissioning of the Yuzhno-Russkoye field, slated for December 18, 2007. However, delays mean that this will not be possible, Gazprom said.