Poland has now become a "paraya state" without diplomatic credence.
If they cannot provide diplomatic status to a foreign leader, what can one say about "White Collar Diplomacy" of EU.
Their representatives should be banned for, at least 6 months, attending EU meetings or any international forum.
Regarding Ukraine, talking about "Diplomacy" is nonnegotiable and they should be banned from entering EU.
NATO for Ukraine is out of the question.