Warsaw - Polish Prime Minister Donald Tusk appealed to the opposition Wednesday to work towards a change in the constitution that would enable Poland to enter the eurozone by 2012.

Poland would need to alter its constitution to allow the European Central Bank to be a monetary authority in the country. Currently the constitution gives the National Bank sole power to distribute money

Tusk has been working to sway Poland's euro-sceptic Law and Justice party, whose support is needed to change the constitution.

"My offer ... sounds like this: let's unlock the constitution," Tusk told radio TOK FM, "so Poland's image in the world and in Europe will be even more stable."

The Polish government recently adopted a road map to enter the eurozone by 2012, but Tusk must still overcome skepticism. He failed to win over Jaroslaw Kaczynski, head of the opposition Law and Justice party, at a recent meeting in Warsaw, but said he would continue talks.

Tusk surprised many analysts when he announced his government would work to adopt the currency by 2012. He said the global financial crisis gives Poland stronger reasons to join the area.

But he lashed out Wednesday at the opposition and President Lech Kaczynski, who has called for a referendum on the issue.

"At times I have the impression that opposition leaders and the president feel a particular satisfaction," Tusk said, "when they can interfere in some project that I support."

Law and Justice has said they'll begin gathering signatures in support of a referendum if they can't convince Tusk to hold one during upcoming European Parliament elections. (dpa)