The farmers say the rules to protect soil sub-structure by banning the use of heavy machinery in damp conditions, such as this summer, are directly blocking their ability to collect the harvest.

This year's crop is one of the worst in recent years, after cool weather stunted growth, but the machinery rules and prolonged rain mean the crops may rot in the wet fields before they can be collected when the weather breaks.

To date around 15 per cent of the wheat crop has been harvested compared to over 50 per cent this time last year, according to official figures.

Guy Gagen, chief arable adviser at the National Farmers Union, said farmers could be fined thousands of pounds if they broke the heavy machinery rules.

"They [the Government] say it is to protect soil structure but when you have thousands of pounds worth of crops in the field you have to get it harvested. You can restore any ruts later.

"It is an enormous frustration. This rule was put in when food production was not considered important and now that is clearly not the case.

"Farmers will technically be breaking the law and facing a fine if they harvest their fields when it is wet."

A spokesman for Defra said the measure to stop farmers from using motorised vehicles on waterlogged soils was introduced to "protect soils from compaction and structural damage caused by using vehicles when the soil is too wet".

However he added that ministers might consider lifting the restrictions.

He said: "We understand the problems that farmers are currently facing with this year's harvest and remain in close contact with the NFU. Hopefully with the arrival of drier weather this week farmers will be able to make progress with the harvest. However, if a request is received we will of course consider it on its merits."

Source: Telegraph