Russian invading forces have stolen “several hundred thousand tons” of grain in territory they hold, Ukraine’s deputy agriculture minister said on April 30.

“Today, there are confirmed facts that several hundred thousand tons of grain in total were taken out of the Zaporizhzhya, Kherson, Donetsk, and Luhansk regions,” Taras Vysotskiy told Ukrainian TV.

Ukraine is one of the world’s major grain producers and the Russian invasion has curtailed exports, pushing up world grain prices and raising concerns about severe grain shortages in importing countries.

Ukrainian Agriculture Minister Mykola Solskiy said grain theft had increased in the last two weeks.

“I personally hear this from many silo owners in the occupied territory. This is outright robbery. And this is happening everywhere in occupied territory,” the ministry quoted Solskiy as saying.

He said such a situation could create food problems in areas that are currently not controlled.

“There will soon be a wheat harvest in the south. But farmers in this situation may well say: ‘Here are the keys to the tractor — go collect it yourself, if you want’,” Solskiy said.

The Kremlin denied Ukraine’s allegations, saying it did not know where the information was coming from.