“Poland will not allow Ukrainian grain to flood us. Whatever the decision of Brussels officials, we will not open our borders,” Morawiecki said in a social media post on Saturday.

The EU in May enacted the ban on imports of wheat, corn, rapeseed and sunflower from Ukraine to neighboring Poland, Hungary, Slovakia, Romania and Bulgaria. The embargo in June was extended to Sept. 15.

The temporary move was meant to protect farmers in those five countries from bulk imports of Ukrainian goods that would cause local prices to plummet and increase competition.

Russia in June terminated a deal allowing Ukraine to export grain shipments from its ports on the Black Sea.

The result is that Ukraine must now rely on EU-sanctioned routes inland to get its grain to markets, meaning nearby countries like Poland face an influx of cheap agricultural goods, to the dismay of local farmers.

Poland was the first country to enact a ban on Ukrainian grain imports after farmers there voiced their concerns.

Lawmakers in Bulgaria Thursday voted to allow the resumption of Ukrainian grain imports. Prime Minister Nikolai Denkov said the government would ask the European Commission to provide compensation for farmers, with the move expected to result in lower food prices.

“Possible unilateral restrictions on the part of Poland will be a violation of the Association Agreement, violation of the conditions of the free market and the basic principles of free trade,” Ukrainian presidential aide IIhor Zhovkva told reporters Thursday, ahead of Poland’s decision.

“We expect a balanced and reasoned decision of the European Commission not to renew restrictions after 15 September, and again, we urge Poland to support this smart step.”