The proposed deal, which fits into PKN Orlen’s strategy, will accelerate the development of its hydrocarbon exploration and production segment.

PKN took the support of its advisers to perform a due diligence examination of TriOil’s assets and its financial, tax, legal, technical, as well as environmental situation, before making the offer.

PKN Orlen CEO Jacek Krawiec said on completion of the transaction the company will gain access to producing fields and will diversify its asset portfolio geographically.

"Further, we continue to retain our strong commitment to shale gas exploration projects in Poland. We have just completed our eighth well and are preparing for another hydraulic fracturing operation at Berejów in the Lublin region," Krawiec added.

In 2012, TriOil’s hydrocarbon production increased by 65% year over year.