WARSAW, Feb 5 (Reuters) - Polish gas monopoly PGNiG said on Tuesday it and four other state-controlled companies had missed a deadline this week to work out how to cooperate in developing the country's shale gas resources but would continue negotiations.
PGNiG, copper miner KGHM and utilities PGE , Tauron and Enea agreed last July to spend 1.7 billion zlotys ($552.88 million) on joint exploration and extraction of shale gas.
They had originally aimed to work out details by early November but pushed that back to February 4.
"Our partners asked us to sign an appendix to the agreement," PGNiG spokeswoman Joanna Zakrzewska said on Tuesday.
"Negotiations continue and like other business talks of this type, they are not the easiest ones. We want to pinpoint the cooperation principles precisely. We do not rule out that the role of PGNiG will change," she said.
Poland has Europe's most ambitious plans for shale gas as a means of reducing its dependence for natural gas on Russia, which supplies the majority of Poland's annual consumption of some 14 billion cubic metres.
Its shale plans have suffered setbacks, however, after the country's estimated recoverable reserves were slashed by 90 percent and U.S. oil major ExxonMobil dropped plans to explore for shale in Poland.
Potential investors have also complained about a lack of clarity in laws in Poland where a new shale gas law is still in the works.
Poland has pegged its recoverable shale gas reserves at 346 billion to 768 billion cubic metres, well below an earlier estimate of 5.3 trillion by the U.S. Energy Information Association.
$1 = 3.0748 Polish zlotys Reporting by Agnieszka Barteczko; editing by Jason Neely