The soaring cost of fertiliser has prompted a "massive dilemma" for Norfolk farmers over whether to invest in feeding this year's crops.

The war in Ukraine has caused upheaval in world commodity markets, ramping up the price of fuel and nitrogen fertiliser, which is linked to gas production.

Kit Papworth runs a contracting business in north Norfolk which works across 1,250ha of arable land, of which 1,000ha is combinable crops.

With fertiliser hitting £1,000 per tonne - compared to its usual £250-£300 - he said farmers face a difficult choice over whether to use it or not.

They can either feed this year's crop to take advantage of high wheat prices, he said, or they can accept a reduced yield this harvest and save some fertiliser for next year - when the cost could be even higher.

"Your instinct is to feed the crop growing in the ground right now, because the price you can sell that crop for is extremely high at the moment," he said.

"But the fertiliser is produced from gas and a hell of a lot of that is coming out of Russia, so I struggle to believe the fertiliser market will return to normal next year.

"Fertiliser prices are rising every day and a lot of people are seriously thinking about reducing their applications this year, so they have some left for next year. But that has the net effect of reducing yield for this harvest.

"So farmers have this massive dilemma over how to manage the risk.

"The wheat price is high, but our margins are actually lower than they were in 2019.

"Using fertiliser now brings your margin back, but you have risked far more cash. So do you save the fertiliser you have got, or do you hope that this is all over soon or the government steps in to help the country produce food? That is where the food security discussion comes in."

Mr Papworth said unless the situation is resolved it will "definitely impact on cropping decisions for the autumn". He added: "Even if the war was to stop tomorrow, I don't see Russia turning the gas tap back on so we are probably years away from resolving these problems."

He also said the "crazy" cost of subsidised red diesel for farm machinery - which has also leapt from 80p per litre to more than a £1 in recent days - was another factor which meant contracting rates would need to increase this spring.