* Budget talks, election may stir trouble *
Polish Prime Minister Donald Tusk promised "energetic engagement" as he took over the rotating presidency of the European Union on Friday and said the 27-country bloc was facing one of its most difficult moments.
Poland, Europe's sixth most populous country and a powerhouse of the central and east European economy, says it wants to strengthen the single market, press ahead with EU enlargement and deal openly with issues such as migration during its six-month presidency, its first since joining the EU in 2004.
Speaking to the foreign press as he prepared to take the reins, Tusk conceded the EU, and particularly the euro zone, faced challenges in tackling the debt crisis that has struck Greece, Ireland and Portugal.
"I'm not going to say these are the most difficult months in the EU so far, but they are definitely some of the more difficult and complicated ones," he said, adding that his aim was to be active and energetic in engaging with his partners.
"Poles don't want politicians who engage in rows with Europe. They want politicians who know how to operate in Europe, who can engage with Europe on a business level and who operate professionally. That's my ambition," he said.
As well as finalising Croatia's EU accession, Poland wants to start membership talks with Serbia and clinch a trade deal with Ukraine, and promote deeper energy and military cooperation within the bloc.
Pushing his pro-European credentials — polls show around 80 percent of Poles like EU membership — Tusk admonished EU leaders who tap into growing euroscepticism in their countries to boost their popularity, although he named no names.
"Too often we see the red light, the red light of exaggerated national accents," he said, saying what bothered him was those who profess to be pro-European but don't hold that line when it comes to restive and sceptical electorates.
"I hope the Polish presidency is going to mean a revitalisation of the European spirit," he said.
Poland will hold an election in October, midway through its presidency, and some fear the campaign will distract Tusk and his ministers from steering the Union through difficult times.
But polls give Tusk's ruling centrist Civic Platform strong lead, making a change of power unlikely.
At a handover ceremony with Hungarian Prime Minister Viktor Orban, who has run the EU agenda for the past six months, Orban talked up the two nations as the new engines of Europe.
"The driving force for the economic growth for all of Europe will be central Europe, just as during the crisis, the GDP growth was higher in CEEU than in other parts," he said.
SUCCESS STORY
Poland, with a population of 38 million and a steady growth rate of around 3.5 percent, is at pains to present itself as a modern EU success story among the ex-communist states, which managed to avoid recession in the 2008-9 global financial crisis.
"We have received a lot from the EU over the last few years and now it's time to give as much as possible from what is our strength based on our national success — we should share our Euro-optimism," Poland's President Bronislaw Komorowski told a special sitting of parliament on Friday.
But the huge challenges facing the EU will test Polish optimism and ingenuity to the full in coming months.
EU leaders are on constant alert about the risk of contagion from Greece's debt crisis to other euro zone member states. Poland, as a non-euro member, will find it difficult to play a role in shaping the response to the crisis which is driven by the 17 countries that share the single currency, but Tusk indicated it aimed to be involved.
He said his finance minister, Jacek Rostowski, would attend euro zone finance ministers' meetings in an "informational" capacity, and described Greece as a victim of the crisis not a co-creator, a position many euro zone leaders would dispute.
Other challenges include difficult negotiations over the EU's next long-term budget, due to start under the Polish presidency. The issue pits poorer countries like Poland that favour generous funds against net contributors to the budget such as Germany and Britain that want to save more money.
Poland, which depends on highly-polluting coal for almost all its energy needs, also upset Brussels recently by blocking an attempt by all other 26 member states to agree a more ambitious plan to curb the bloc's greenhouse gas emissions.
