Disruption to global fertiliser supplies caused by the war in Iran could put further pressure on food prices and hit poorer countries hardest, according to the boss of one of the world’s biggest fertiliser producers.

Yara chief executive Svein Tore Holsether warned that hostilities in the Gulf, which have blocked shipping through the Strait of Hormuz, are threatening global food production by disrupting supplies of fertiliser and its key ingredients.

Holsether told the BBC that reduced fertiliser use could lead to lower crop yields and trigger a bidding war for food between richer and poorer nations.

“We’re up to half a million tons of nitrogen fertiliser not being produced in the world right now because of the situation we are in,” he said.

“What does that mean for food production? I would get to up to 10 billion meals that will not be produced every week as a result of the lack of fertilisers.”

Holsether said failing to apply nitrogen fertiliser could reduce yields for some crops by as much as 50 per cent in the first season.

While the UK is not expected to face food shortages, the increased costs facing food producers are likely to filter through to supermarket shelves in the coming months.

The price of fertiliser has surged by 80 per cent since the beginning of the US and Israel’s war on Iran, adding further pressure to farmers already grappling with higher input costs.

Holsether said farmers were facing “higher energy costs”, rising diesel prices and increasing fertiliser costs, while crop prices had not yet risen enough to offset the squeeze.

He warned that a prolonged conflict could result in wealthier countries outbidding poorer nations for food supplies.

“If there’s a bidding war on food and one that Europe is robust enough to handle, what we need to keep in mind in Europe is, OK, in that situation, who are we buying the food away from?” he said.

“That is a situation where the most vulnerable people pay the highest price for this in developing nations where they cannot afford to follow that.”

The Yara boss said the situation carried major implications for “food affordability, food scarcity and hunger”.

The Food and Drink Federation recently forecast that food inflation could reach 10 per cent by December, while the Bank of England said this week that food price inflation could rise to 4.6 per cent in September and potentially move higher later in the year.

The UN World Food Programme has estimated that the combined fallout from the Middle East conflict could push an additional 45 million people into acute hunger in 2026.

Food insecurity across Asia and the Pacific is expected to rise by 24 per cent, the largest relative increase of any region.

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