WARSAW, Poland (AFP)— Poland and Ukraine Tuesday summoned each other’s’ envoys over an escalating row between the allies on grain imports from Kyiv.

Polish presidential aide Marcin Przydacz on Monday said Warsaw was prioritising “the interests of Polish farmers” when it called on the EU to extend a ban on imports of Ukrainian grain.

“Ukraine received a lot of support from Poland, it would be worth it, if it started to appreciate the role Poland has played for Ukraine in recent months and years,” Przydacz added.

Kyiv reacted by summoning Poland’s ambassador to the Ukrainian foreign ministry on Tuesday.

“The statements about the alleged ingratitude of the Ukrainians… do not reflect reality and as such are unacceptable,” the Ukrainian side said in a statement.

Poland reciprocated by summoning Ukraine’s envoy, Vasyl Zvarych, to the foreign ministry but later said his deputy would be hosted on Wednesday as Zvarych is currently in Kyiv.

Warsaw is among Ukraine’s staunchest allies as Kyiv fights off the Russian invasion. But tensions between the neighbours grew as Poland opposed Ukrainian grain imports that had been triggering protests from local farmers.

The 27-nation European Union dropped duties on Ukrainian exports in the wake of Russia’s all-out invasion to help Kyiv earn vital revenues.

But EU countries along the border of the global agricultural powerhouse started barring imports after their farmers protested that a glut of Ukrainian grain was pushing down prices.

In June, Brussels agreed to allow Poland, Bulgaria, Hungary, Slovakia and Romania to restrict imports of grain from Ukraine through September.

In July, Poland urged the European Union to extend the grain import ban that is set to expire on September 15, and threatened to otherwise maintain it unilaterally.