The move was initiated by Polish Prime Minister Mateusz Morawiecki, who has previously criticised the EU executive for failing to deliver on its promise to send grain imported from Ukraine to Middle Eastern and African countries, Poland's PAP news agency reported.
Some of the grain exports remain in the countries neighbouring Ukraine, including Poland, and farmers have complained that they have problems selling their own grain due to full warehouses and decreasing prices.
In a letter addressed to European Commission chief Ursula von der Leyen, Poland's Morawiecki and the leaders of Bulgaria, Hungary, Romania and Slovakia wrote that "the Russian aggression against Ukraine has not only led to a huge increase in production costs in the agricultural sector and an increase in business risk, but also to problems on the agricultural EU markets."
However, these difficulties "are not even" across Europe, they argued.
"The most severe disturbances are experienced in countries that border Ukraine or are in close proximity to it," they wrote. "These problems are related to a substantial increase in the supply of Ukrainian products to the markets of the EU Member States, especially those bordering or close to Ukraine."
The letter also stated that there were difficulties in "disposing of the surplus cereals in storage," which it said has destabilised the markets for cereals, industrial and oilseed crops, especially wheat, maize, rape and sunflower, and imposed additional costs on agricultural producers.
According to the five leaders, given the scale of the problems caused by the Russian war on Ukraine, some form of restrictions on the volume of Ukrainian grain imports needs to be introduced.
"On trade mechanisms, we propose to amend the current legal basis for agricultural imports from Ukraine to introduce the possibility of regulating the volume and direction of excessive inflows of agricultural products," they wrote.
In addition, the five leaders called for increased financial support for farmers, the PAP news agency reported.
They argued that "it is necessary to significantly increase the amount of EU funds allocated to EU support measures."
Additional funds are needed because the EU's Common Agricultural Policy and national budgets "are insufficient," the letter said.
Its signatories called for new sources of funding, in addition to planned emergency measures, to support agricultural producers who have suffered losses and are at risk of losing financial liquidity, the Polish state news agency reported.