A historical dispute between Warsaw and Kiev continues to smoulder unresolved, dividing Polish foreign policy.
Prime Minister Donald Tusk said in Warsaw on Tuesday that the Ukrainian side must take responsibility for the crisis and, consequently, for finding a way out of it.
At the same time, he asked conservative Polish President Karol Nawrocki not to allow the conflict with the neighbouring country to escalate.
There was initially no reaction from Kiev to the comments made in Warsaw.
Ukrainian President Zelensky sparked the dispute at the end of May when he bestowed the nickname "Heroes of the UPA" on an army unit.
Kiev honours the memory of the underground fighters of the Ukrainian Insurgent Army (UPA) because they resisted Soviet rule after World War II. During the war, however, the armed fighters carried out massacres of tens of thousands of Poles in what is now western Ukraine.
In Poland, the honouring of the UPA met with cross-party outrage, and Nawrocki said that Zelensky should be stripped of the Polish Order of the White Eagle.
Over the weekend, Zelensky’s Chief of Staff Kyrylo Budanov had spoken in Warsaw with representatives of the government and the presidential office, without any resolution to the dispute emerging.
The row comes at a particularly inopportune moment. A reconstruction conference for Ukraine is due to take place in the Polish city of Gdańsk on June 25 and 26, involving the EU, the G7 and other donors. Poland and Ukraine are co-hosting the event.
