"Export of food and grain from Ukraine is extremely critical," Jens Stoltenberg told reporters in Brussels. "The spike in food and grain prices shows global ramifications of this war."

"Russia tries to create narrative that spike in grain prices is caused by our sanctions — that's not correct."

The secretary-general said international efforts are ongoing to try and lift the Russian blockade of Black Sea ports to allow the export of Ukrainian grain — with Turkey a key player in the negotiations

He added: "There are some efforts to get some grain out over land - NATO countries are involved in that."

Earlier this week UN Human Rights chief Michelle Bachelet warned of a sharp increase in global food insecurity as the war in Ukraine continues.

Building temporary silos in Poland for

Ukrainian grain may take four months

Poland’s agriculture minister said a US plan to build temporary silos on the border with Ukraine to store Ukrainian grain and facilitate its export through Polish ports will take three to four months.

Henryk Kowalczyk told Polish TV that Ukraine would normally expect to export around five million tons of grain per month but the Russian blockade of its ports was preventing supplies from leaving by sea.

Tuesday, US President Joe Biden said Washington plans to construct temporary silos in countries bordering Ukraine, including Poland.

They are needed for storage on the border because Ukraine’s railway gauge is wider than EU rail networks and the grain must be offloaded at the border before it can be reloaded on wagons en route to Polish seaports.

Kowalczyk said import capacity at the Polish border is currently limited to about 1.5 million tons per month but the construction of the silos would make the process smoother.

However, he said there is also a lack of grain containers and handling equipment.

“If we do not deliver grain to North Africa, to Middle Eastern countries, there will be hunger and a wave of migrants will flow to western Europe,” Kowalczyk said.