KIEV, Feb. 17 – State-owned Naftogaz Ukrayiny and U.S.-based ExxonMobil have signed a memorandum on cooperation in the exploration of unconventional hydrocarbon reserves in Ukraine, according to the Ukrainian Energy and Coal Industry Ministry.

"The signed memorandum is aimed at initiating mutually beneficial cooperation between the companies in analyzing potential stocks of methane in coal deposits, shale gas, gas found in rock formations, and other types of hydrocarbon of unconventional origin," reads a press release.

The document was signed during a meeting between Ukrainian Energy and Coal Industry Minister Yuriy Boyko and the top managers of ExxonMobil and Chevron in Houston, the United States, on February 16.