The European Commission has warned that Europe faces another migration wave from the Middle East and Africa because of the food crisis created by the war in Ukraine.

Ukraine is one of the world’s largest grain exporters but production and export have been significantly curtailed by Russia’s invasion.

Almost 20 million tonnes of grain from last season’s harvest is blockaded in Ukrainian ports on the Black Sea.

The war in Ukraine has sent prices for some grains and cooking oils soaring on world markets, with Africa and the Middle East bearing most of the brunt.

A spokesperson for Europe’s border agency Frontex has said that while Ukrainian refugees are being supported, “we have to prepare also for refugees coming from other areas because of the food security”.

The spokesperson Aija Kalnaja said: “grain transport from Ukraine is hampered, and that will create waves of migration”.

Ms Kalnaja was speaking in Prague at a meeting of EU interior ministers that has been expanded to also include the ministers from non-EU countries Ukraine and Moldova.

Meanwhile, Russia has said it would allow Ukrainian freighters to leave the ports if Ukraine demined the coastal areas – something Kyiv refuses to do because of how vulnerable it would leave it to seaborne Russian assaults.

The head of UNHCR, Filippo Grandi, warned in June that unless the growing food crisis caused by Russia was quickly resolved, the number of displaced people globally would swell well beyond the record 100 million reported in the latest UN figures.

The war in Ukraine, which began in February, has already sparked the largest refugee outflow in Europe since World War II, prompting the EU to offer fleeing Ukrainians temporary protection.

According to the UN, the 27-nation European Union is hosting 5.6 million Ukrainian refugees.

Poland has the largest number with 1.2 million, while the Czech Republic has 400,000, the largest proportion on a per capita basis.

Frontex says that the outflow of Ukrainians has slowed in recent weeks and are described as similar to pre-war levels.

The agency says that many of the Ukrainians in the EU were expected to make decisions on whether or not to return to their country in the next couple of months, before school resumes after the summer break.

In 2015, the Syrian and Iraq conflicts saw 1.3 million people enter Europe to request asylum, the largest number in a single year since World War II.

Most came from Syria, but many others came from Iraq, Afghanistan, Nigeria, Pakistan and Eritrea.

Europe had already begun registering increased numbers of refugee arrivals as early as 2010, due to a perfect storm of conflicts in parts of the Middle East, Asia and Africa – and particularly the wars in Syria, Iraq and Afghanistan. The terrorist insurgencies in Nigeria and Pakistan and long-running human rights abuses in Eritrea also contributed to refugee flows

In 2015, the vast majority of refugees arriving in Europe came by crossing the Aegean Sea from Turkey to Greece, making their way overland through the Balkans and into the European Union.

Previously, most refugees had reached Europe by crossing the Mediterranean Sea from Libya to Italy, largely due to the collapse of border controls during the Second Libyan Civil War.