Polish nationalist opposition candidate Karol Nawrocki won the second round of the country's presidential election with 50.89 per cent of the votes, the electoral commission said early on Monday on its website.
His rival, Rafal Trzaskowski, the liberal Warsaw mayor and an ally of the government led by Donald Tusk, got 49.11 per cent.
Nawrocki, 42, a eurosceptic historian and amateur boxer who ran a national remembrance institute, campaigned on a promise to ensure economic and social policies favour Poles over other nationalities, including refugees from neighbouring Ukraine.
While Poland's parliament holds most power, the president can veto legislation, and the vote was being watched closely in Ukraine as well as Russia, the United States and across the European Union.
On social media platform X, current President Andrzej Duda, also a conservative, thanked Poles for going to vote in large numbers. Turnout was 71.31 per cent, the electoral commission said, a record for the second round of a presidential election.
"Thank you! For participating in the presidential elections. For the turnout. For fulfilling your civic duty. For taking responsibility for Poland. Congratulations to the winner! Stay strong Poland!" Duda wrote.
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