One year into his second term in office, Poland's centrist Prime Minister Donald Tusk has called a confidence vote for Friday to confirm his coalition's mandate as it tackles a slowing economy amid a surge in popularity for the opposition.

Tusk said Thursday he was "convinced the confidence vote will confirm the mandate that we received from voters" in last October's general election.

That vote saw his Civic Platform (PO) team up with the agrarian Polish People's Party (PSL) to take what is now a slim four-seat majority in the 460-seat lower house of parliament.

Tusk's administration is also facing growing social discontent as Poland's relatively good economic performance slows amid the Europe-wide downturn. The conservative Law and Justice (PiS) opposition led by Jaroslaw Kaczynski came out on top in a recent opinion poll.

Two separate surveys published this week showed Tusk's PO garnering 28 and 33 percent popular support, compared to 24 and 39 percent backing for the PiS.

The confidence vote will go ahead in parliament Friday after Tusk is due to address parliament to outline how his government aims to preserve Poland's relatively good economic performance next year amid the Europe-wide downturn.

"In Poland, we're feeling an ever greater economic menace, but I'm convinced that my address tomorrow will demonstrate the precise, good and trustworthy plan we have in store for Poland," Tusk said late Thursday.

With a population of 38.2 million, Poland was the only EU state that managed to sustain growth throughout the last global crisis. Output tallied at 4.3 percent in 2011 after 3.8 percent in 2010. The government has forecast growth of 2.5 percent this year, edging down to 2.2 percent in 2013 under the expected impact of the eurozone debt crisis. The most recent jobless rate stands at 12.5 percent.