Ukraine has filed complaints with the World Trade Organization (WTO) against Poland, Slovakia and Hungary over their bans on food imports from Ukraine, a senior government minister in Kyiv has said.
Yulia Svyrydenko, first deputy prime minister, said Ukraine saw such restrictions as a violation of the European Union countries' international obligations.
"For us, it is critically important to prove that individual member-states cannot ban imports of Ukrainian goods. And that is why we have filed suits through the WTO," Ms Svyrydenko said in a statement.
"At the same time, we hope that these states will rescind their restrictions and there will be no need for us to settle our relations in the courts over long period of time," she said. "We need solidarity with them and to defend the interests of farmers."
Restrictions imposed by the EU in May allowed Poland, Bulgaria, Hungary, Romania and Slovakia to ban domestic sales of Ukrainian wheat, maize, rapeseed and sunflower seeds, while permitting transit of such cargoes for export elsewhere.
Poland, Slovakia and Hungary announced their own restrictions on Ukrainian grain imports on Friday after the European Commission decided not to extend its ban.
The three countries said they were acting in the interests of their economies and their moves are intended to protect their farmers from a glut of products.
Poland, with a parliamentary election looming in October, distanced itself even further and withdrew from a coordination platform - a group including the five neighbours, Ukraine and the European Commission - that has been looking at solutions to boost Ukraine grain transit to global markets.
"We have to look forward, since Ukraine said it wants to sue Poland ... every comment we would have made on this platform could be used against us," Polish Agriculture Minister Robert Telus told reporters in Brussels.
For much of the last year, some 60% of Ukrainian grain has transited through the five EU countries using so-called Solidarity Lanes as an alternative to the Black Sea due to Russian threats.
Like most countries in central and eastern Europe, Poland and Slovakia have been some of Kyiv's strongest allies in its fight against Russia's invasion that began in February 2022.
Hungary's stance has been more ambivalent, as the only member of the EU and NATO alliance to maintain close relations with Moscow, still the main source of its oil and natural gas.
But grain exports have been an area of friction throughout the region.
