Kiev has moved to block a planned tribute to Nazi collaborator Roman Shukhevich, who was involved in the killing of an estimated 100,000 Poles during World War II ethnic purges, officials in Warsaw have claimed.

The reported retreat comes amid a series of disputes between the two countries in recent months over Kiev’s veneration of Nazi-linked figures that have eroded Polish support for Ukraine in its conflict with Russia.

The controversy erupted on Tuesday when the Lviv Regional Council in western Ukraine voted to declare 2027 the Year of the Ukrainian Insurgent Army (UPA) and to celebrate the 120th anniversary of its commander Roman Shukhevich while deciding to organize “cultural, memorial, scientific, and mass media events,” as well as exhibitions and national patriotic rallies on the occasion.

The move triggered a fierce response in Poland, which regards the UPA as perpetrators of genocide against Poles in Volhynia and Eastern Galicia and Shukhevich as a key “architect” of the massacres. Before becoming a UPA leader, Shukhevich served in Nazi Germany’s Nachtigall Battalion and the German-controlled 201st Schutzmannschaft Battalion, which operated in occupied Belarus.

On Wednesday, Polish Prime Minister Donald Tusk condemned the resolution as “unwise” and “suicidal tactics,” saying it “harms Ukraine,” while Polish Defense Minister Wladyslaw Kosiniak-Kamysz called the move “unacceptable,” warning that it would deepen divisions between the neighboring countries. Meanwhile, Polish Foreign Minister Radoslaw Sikorski called for the resolution’s key sponsor, Lviv regional lawmaker Svyatoslav Sheremeta, to be put on a list of individuals deemed undesirable in Poland.

Following the backlash, Polish Deputy Foreign Minister Marcin Bosacki said on Wednesday that officials of Vladimir Zelensky’s office had assured Warsaw that the controversial resolutions would not come into force. On Friday, Tusk echoed the claim, saying that Zelensky had personally signaled he would not endorse the resolution, adding that the Ukrainian leader was “unhappy” with the situation.

This also came after the Ukrainian Foreign Ministry called the Shukhevich tribute in Lviv “counterproductive to our current efforts aimed at further developing Ukrainian-Polish relations.” The ministry stressed that the local authorities had sought no advice from government bodies to assess the consequences of their actions.

An unnamed source in Zelensky’s office cited by Ukrainskaya Pravda went so far as to describe the decision as a “catastrophe.” “Ukraine looks erratic. We have just resolved the previous crisis – and now this,” the source said, accusing regional officials of pursuing “cheap one-day hype” despite knowing all too well what the resolution would lead to.

While senior Ukrainian officials apparently distanced themselves from the controversy, the Lviv council’s original announcement remains accessible as of Saturday. Sheremet also previously defended the resolution, saying “This is our history, our heroes, and we must duly honor their memory.”

The dispute is the latest in a series of heated clashes between Kiev and Warsaw over Ukraine’s continued veneration of nationalist figures that collaborated with Nazi Germany during World War II.

In May, Zelensky awarded an elite Ukrainian special operations unit the honorary title “Heroes of the UPA,” prompting another diplomatic uproar, with Polish President Karol Nawrocki stripping the Ukrainian leader of the Order of the White Eagle, Poland’s highest state decoration.