EU is in a very tough spot right now. They're getting squeezed on all sides economically by USA and China while simultaneously facing a Russian invasion on their eastern borders. The relationship with the American administration has deteriorated badly and any action seen as "retaliation", such as this policy blockade, would almost definitely result in USA withdrawing even more support for Ukraine in the war. I think, unfortunately, that will lead to a quick victory for Russia unless EU nations want to put boots on the ground.

It's a bad situation.