EU relations with Poland may be heading for difficulty after the conservative, EU-critical mayor of Warsaw, Lech Kaczynski, came from behind to be elected president last night.

His campaign turned dirty last week as he cranked up anti-German rhetoric in an attempt to win votes of older Poles with memories of the second World War. Mr Kaczynski published a report claiming that the Nazis caused damage worth at least EUR 45 billion during the occupation and destruction of the Polish capital.

Mr Kaczynski also suggested Mr Tusk, who has close relations with Chancellor-designate Angela Merkel, would be too "ready to compromise" with Germany.

Mr Kaczynski (56) snatched victory from liberal favourite Donald Tusk in the final days of the campaign to take 52 per cent of the poll, according to exit polls last night.

His victory completes a political shift to the right in Poland, and mirrors last month's general election success of his twin brother Jaroslaw who lead their Law and Justice Party (PiS) to victory by overtaking Mr Tusk's Civic Platform (PO) in the final days of the campaign.

Mr Kaczynski ran a highly effective campaign, promising to eradicate Poland's rampant corruption, promote traditional moral values and create a new "fourth republic", a French-style presidential democracy.

Last night's result showed how his policies found favour far beyond his traditional stronghold of highly conservative, religious voters in rural areas.

The key to Mr Kaczynski's victory was the backing he secured in recent days from right-wing candidates eliminated in the first round, as well as the endorsement of the radical right-wing religious radio station Radio Maryja.