Polish President Lech Kaczynski said he will not sign the European Union's Lisbon Treaty, calling the issue "pointless" after Ireland's rejection of the text in a referendum last month, reported dpa.
Kaczynski was quoted by the daily Dziennik on Tuesday as saying that he would not endorse the treaty until Ireland changed its stance and made the decision on its own, without giving in to pressure from other EU members.
"It's hard to say how this will end," he told the daily. "However, it's flippant to say since there is no treaty, there is no union."
Kaczynski said similar concerns about the functioning of the bloc had been voiced after a proposed EU constitution was rejected by French and Dutch voters in 2005, but that the EU had still managed to work, is working and will continue to work even - if it's not ideal.
He also warned that Ireland should not be pressured into making a decision that was not its own.
"If the rule of unanimity is broken once, it won't exist ever again," Kaczynski said.
Reacting to the news in Brussels, officials from the European Commission urged Poland to go ahead with the ratification process, noting that President Kaczynski had not only signed the treaty, but had also emerged as one of its chief protagonists during its negotiating phase.
"Poland, like other member states, has signed the treaty and has committed itself to ratifying it," said Pia Ahrenkilde Hansen, a spokeswoman for the EU executive.
The official also noted the conclusions of last month's EU summit in Brussels, in which all 27 leaders agreed that despite the Irish no to the treaty, "the ratification process continues in other countries."
Poland's parliament ratified the treaty in April and Prime Minister Donald Tusk has said the EU will look for ways to bring the treaty into effect, despite the Irish rejection.
But the document needs Kaczynski's signature and ratification from all 27 EU members.
Kaczynski has long been sceptical of the treaty, but some Polish politicians were surprised when he called it "pointless" to sign and said it reflected Poland's changed view on the future of the EU.
"Such a viewpoint is surprising to me," Vice Premier Grzegorz Schetyna told TOK FM. "It's something that's a change in Poland's entire thinking and view of the future of the European Union and our place in Europe."
Kaczynski's announcement was seen as a blow to Nicolas Sarkozy, who took over the rotating presidency of the EU on Tuesday and who said he was looking for a solution to the treaty's rejection.
So far, 19 national parliaments have endorsed the treaty. However, the ratification process has to date only been formally completed in 11 member states.
Aside from Poland, the ratification process has also been suspended in Germany and the Czech Republic, pending pronouncements by the countries' constitutional courts.