Poland has accused Kiev of making unacceptable “suicidal” moves after the Ukrainian city of Lviv dedicated 2027 to the Ukrainian Insurgent Army (UPA) and its leader, Nazi collaborator Roman Shukhevich.

To celebrate the 120th anniversary of Shukhevich’s birth and mark 85 years since the creation of the militant group that perpetrated mass killings of ethnic Poles, Jews, and Russians, the Lviv Regional Council decided on Tuesday to organize “cultural, memorial, scientific, and mass media events,” as well as exhibitions and national-patriotic rallies.

The announcement was met with widespread condemnation in Poland, which regards the UPA as perpetrators of genocide against Poles in Volhynia and Eastern Galicia and its leader, Shukhevich, as a key ‘architect’ of the massacres. From 1943 to 1945, Ukrainian nationalist militants murdered an estimated 100,000 ethnic Poles in the regions, which are now largely part of modern Ukraine.

Polish Prime Minister Donald Tusk called the move a “suicidal tactic,” and Defense Minister Wladyslaw Kosiniak-Kamysz called it “unacceptable.” Foreign Minister Radoslaw Sikorski condemned the announcement, calling for the resolution’s key sponsor, Lviv regional lawmaker Svyatoslav Sheremet, to be placed on Poland’s travel ban list.

The Ukrainian Foreign Ministry attempted to downplay the incident, blaming the Lviv regional authorities for making the “harmful decision.” The ministry also said the regional council did not consult any central authorities regarding “the consequences of their actions for bilateral relations with Poland.”

The resolution ultimately vanished from the Lviv council’s website without any explanation. Speaking to Polish media on Wednesday, Deputy Foreign Minister Marcin Bosacki said Warsaw received assurances from Kiev that the resolution would not be implemented.

“We take on faith the words of the administration of Vladimir Zelensky that this catastrophic decision will not be implemented,” Bosacki stated, calling the disappearance of the resolution from the council’s website a “good sign,” but cautioning against interpreting it as an official cancellation of the celebrations.

Ukraine’s increasingly open honoring of WWII-era nationalists and Nazi collaborators has drawn criticism from Warsaw, which remains one of Ukraine’s key backers in the conflict with Russia.

Poland regards the UPA and the Organization of Ukrainian Nationalists (OUN), which collaborated with Nazi Germany during the early stages of its 1941 invasion of the Soviet Union, as perpetrators of genocide, while modern Ukraine cherishes them as freedom fighters and national heroes.

Earlier this year, Ukrainian leader Vladimir Zelensky named a military unit after the ‘Heroes of the UPA’ and established a ‘pantheon of outstanding Ukrainians’ at Kiev’s main military cemetery, where OUN leader and Nazi collaborator Andrey Melnik was reinterred with state honors in May.