Downing Street has intervened in a growing diplomatic spat between Kyiv and Warsaw over the naming of a Ukrainian army unit that fought alongside the Nazis during World War Two. The dispute, which erupted last week when Poland's parliament passed a resolution condemning the Ukrainian Insurgent Army (UPA), has threatened to unravel the fragile unity between two of Britain's key allies in the region.
Senior Whitehall sources have confirmed that officials urged President Volodymyr Zelensky to de-escalate the matter during a phone call on Tuesday. The war in Ukraine, now entering its third year, has made the partnership between Kyiv and Warsaw vital for the transit of Western weapons and grain. Any rift, one source said, was "a gift to Moscow."
The row centres on the UPA, a nationalist militia that fought for an independent Ukraine during the 1940s. While some Ukrainians revere them as freedom fighters, Poles and many historians accuse them of orchestrating the Volhynia massacres of 1943-44, in which an estimated 100,000 Polish civilians were killed. Poland's resolution, passed on July 11, branded the UPA a "criminal organisation" and called for the exhumation of mass graves.
Zelensky, who has previously avoided direct comment on the UPA, called the resolution "unacceptable" and warned it could embolden Russian propaganda. But his pushback has angered Polish nationalists and strained relations ahead of a planned visit to Warsaw for talks on EU membership.
"The mood has soured fast," said a Polish diplomat. "We expected more sensitivity from Ukraine, given the history."
British officials, trying to manage the fallout, have stressed the need for both sides to focus on the shared threat from Russia. "This is a distraction from the real enemy," one said. "The priority is keeping the coalition united."
But the row has touched on deep historical scars that go beyond the current war. For many Poles, the UPA's legacy is still raw, a reminder of an ethnic conflict that remains under-documented in Ukraine. For Ukrainians, the group's image is more nuanced: a symbol of resistance against Soviet oppression, even if stained by atrocities.
Economically, the dispute has already had ripple effects. Polish truckers and farmers have begun blockading border crossings with Ukraine, protesting what they see as unfair competition. The blockades, which started over grain imports, have now been linked by some to the political tension. "The blockade is about trade," said a union leader in Przemysl, "but the mood on the ground has turned meaner since the UPA thing."
For the British government, which has positioned itself as a key backer of Ukraine, the row is an unwelcome complication. The leaders of the Self-Defence of the Polish Nation party, a minority partner in the Polish coalition, have called for a referendum on the issue. "This will not go away," said its chairman.
Downing Street has not commented publicly on the phone call, but officials insist the message was clear: the alliance must hold. "We can't afford fractures," a Whitehall source said. "Not now."
Zelensky's office has not confirmed the conversation. But in a late-night address on Tuesday, he acknowledged the need for "honest dialogue" with Warsaw. "We must not let history divide us," he said. "Russian victory would bring far worse."
Analysts say the episode reveals the delicate balancing act facing Kyiv. "They need Polish support desperately," said Dr. Mateusz Krajewski of the University of Warsaw. "But they also have a domestic audience that sees the UPA as part of their heritage. It's a very difficult line to walk."
For now, the war in the east continues to demand all attention. But the scars of the past are proving hard to bury.
