Last week Poland's No. 2 utility Tauron picked the 5.4 billion zloty ($1.74 billion) bid by Polish boil maker Rafako and builder Mostostal Warszawa to build a coal-fired unit at its Jaworzno power plant.

CNEEC said on Monday its bid was lower at 4.9 billion zlotys adding that it would appeal to Poland's chamber of appeals (KIO) by Feb. 4.

"If it does not have any effect, we will go to court," the Chinese company said in a statement.

State-controlled Tauron, whose power plants are among the most outdated in Poland, planned to sign the deal in the second quarter but the Chinese appeal could delay the process.

Chinese companies are becoming more visible in Poland, with construction firms bidding in tenders for power units launched by local utilities.

Chinese COVEC was forced to abandon its unfinished stretch of a motorway in 2011 when its workers walked off and it turned to Poland for more money.