Government officials pointed the finger at the presidential palace, while opposition politicians argued Poland was deliberately sidelined on the world stage because of government ineptitude.
The absence was notable given Poland's role as a hub for international aid to Kyiv and NATO's top defence spender in relation to GDP.
"I see this as something of a misstep, given that Poland borders Ukraine and that virtually all aid sent there has passed through our country," Wojciech Kwiatkowski, an American studies scholar, told public broadcaster Polish Radio.
"We also took in the bulk of refugees, so leaving Poland out feels, in a sense, like a slight," he said, adding that he believed the decision was not made in Washington but stemmed from Ukrainian President Volodymyr Zelensky "simply not raising the issue of Polish participation."
Michał Owczarek has the story.
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