By Pawel Sobczak
WARSAW (Reuters) - Poland's prime minister paved the way for a referendum on joining the euro, dropping objections to a ballot that could all but extinguish emerging Europe's waning love affair with a currency that has lost much of its lustre.
Adopting the euro has been a central goal for Donald Tusk since he came to power in 2007, and he said that failure to join the currency bloc could leave Warsaw stuck on the periphery of European affairs.
He has consistently opposed a popular vote on the issue, but said on Tuesday he would endorse one as part of a wider bargain with the eurosceptic opposition for changes to a constitution under which only the zloty can serve as Poland's currency.
"I would be in favour of reaching an agreement to change the constitution, where there would be a referendum about joining (the euro zone)," Tusk told a news conference.
Surveys suggest that - mindful of four years of economic turmoil in the likes of Greece, Ireland and Portugal - most of the country's 38 million people would say no.
That makes the thinking behind Tusk's move - whether part of a longer-term plan to adopt the common currency or to shift government policy towards keeping the zloty - not immediately clear.
With Cyprus fighting a costly battle to avoid exiting the euro zone, there may be increased reluctance within the bloc to explore letting a country like Poland, the largest of the European Union's ex-Communist members, join soon.
But the flexibility the zloty provides has been a major factor in Poland maintaining more than two decades of growth, even through an economic crisis in which every other EU country suffered a contraction.
"It looks like the government is trying to push the euro entry date into the future, given the lack of public support," said Rafal Benecki, chief economist at ING Bank Slaski. "And the Cyprus case could only make it worse."
KICKING THE CAN?
Among Poland's ex-communist peers, Slovakia, Slovenia, and Estonia have already joined the euro. Latvia has asked Brussels to start the process, and Lithuania's central bank has said it could join as early as 2015.
Other countries, however, and particularly the Czech Republic, have no plans to join soon and see their freely convertible currencies as one of their main tools to stay competitive and fight economic crisis.
Tusk has in any case said his government would only set a date for euro entry after the next national election, due in 2015.
Analysts see 2019 as the earliest possible date Poland could swap its zlotys for euros.
Under Tusk's previous government, the country postponed plans to push for euro entry several times last decade, and resistance by Poland's opposition to changing the constitution has blocked progress.
Tusk's Civic Platform and his junior coalition partner hold a slim majority in parliament and would need the support of the rightist Law and Justice (PiS) party to reach the two-thirds in the lower house required to change the constitution.
PiS, which has previously said it would oppose euro adoption without a referendum, said it was surprised by the premier's about turn.
"This is a significant change of the Civic Platform's position because up to now its politicians have been saying a referendum is impossible," said Kzysztof Szczerski, PiS deputy responsible for euro-related issues.
(Additional reporting by Dagmara Leszkowicz; Editing by John Stonestreet)