Poland is seen as a prospective market for unconventional gas production, with 90 exploration licences awarded and the likes of Chevron and ExxonMobil among interested parties.

"With moderated optimism we think that in 2014 there will be commercial extraction, so really just around the corner," Tusk said.

He added that by 2035, Poland, which relies almost entirely on gas from Russia, may be able to mainly use its own source.

Decreasing Poland's energy dependence on its eastern neighbour has been a goal for its governments and often an issue in election campaigns. The country holds an election on October 9.

Poland, the European Union's largest ex-communist member, also hopes to capitalise on some of the income from shale gas production through taxes and licences.

According to a recent study by the US Energy Information Administration, Poland's technically recoverable reserves of shale gas are the biggest in Europe, at an estimated 5.3 trillion cubic metres.

Copyright Reuters, 2011