WARSAW, June 21 (Reuters) - A conflict between politicians in Poland and Ukraine is a strategic mistake that will harm both ‌sides, Polish Prime Minister Donald Tusk said on Sunday, seeking ‌to defuse a rekindled dispute over events that occurred during World War Two.

Polish President ​Karol Nawrocki on Friday stripped Ukrainian President Volodymyr Zelenskiy of the country's top honour, prompting three former Ukrainian presidents and other senior officials to return their state awards to Poland.

Nawrocki revoked the Order of the ‌White Eagle after Zelenskiy ⁠angered many in Poland by renaming a Ukrainian army unit after the Ukrainian Insurgent Army, nationalists who massacred ⁠Poles during World War Two.

The pro-European Tusk was reelected as prime minister in 2023, after leading a coalition that defeated the nationalist Law and ​Justice party ​with which Nawrocki is aligned.

"Wading ​into a conflict between politicians ‌in Poland and Ukraine is a strategic mistake that will harm both sides: business-wise, geopolitically, and reputationally. And in politics, as we know, a mistake is worse than a crime," Tusk wrote in a post on X.

"In discussions with my European partners, I strive to minimise ‌losses and reduce tensions. This is ​no easy task," he added.

Zelenskiy, in an ​interview posted on X, said ​Ukraine and Poland cannot be "anything but partners and ‌friends," adding that a political struggle ​could end in ​a "very dangerous escalation".

"Our servicemembers choose a heroic name for their unit themselves, and as President and Supreme Commander-in-Chief, I must support ​them," he said. "Without Ukraine, ‌no one will be able to defend Poland. It is ​simply impossible."

(Reporting by Anna Koper and Jekaterīna Golubkova; Editing ​by Barbara Lewis and Edmund Klamann)