Tusk was commenting on the recent news that Andrzej Duda, the Polish president, might meet Trump, the frontrunner to be the Republican candidate for president, during his visit to the US and Canada, which commenced on Tuesday.
Trump, who is also a former president, is the favourite to take on Joe Biden in November's presidential election.
Tusk said that Trump's possible victory "would probably be to the detriment" of Poland's and Europe's security, and Nato's future.
Thus, he added, if Duda decides to see Trump, he expects the Polish president to "very firmly raise the issue of taking an unequivocal stance on the side of the Western world, democracy and Europe" in the Ukraine-Russia conflict.
According to him, almost every speech by Trump "very clearly shows his rather anti-Ukrainian sentiment, the kind of pro-Russian attitude that we also know from the past, his reluctance to help Ukraine, his blocking of financial aid that was almost voted down in the US, his very critical attitude towards Nato."
A multi-billion aid package, which would constitute the major source of Ukraine's ammunition funding, has been stuck in the US Congress for months as conflicts between Democrats and Republicans have intensified before the presidential election. (PAP)
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