Farmers face being dragged into paying a so-called “mansion tax” in a double whammy blow for the industry, it has been suggested.

Owners of tens of thousands of properties in England valued at more than £2million are set to be hit with a surcharge of at least £2,500 from 2028.

David Bean, parliament and government relations manager for the Countryside Alliance, said: "This Budget has done little to support farmers hit by the Family Farm Tax last year, and we are concerned about the risk of the so-called 'mansion tax' hitting some asset-rich but cash-poor farmers still harder.

“The government claims to understand that food security is integral to national security. It needs a fiscal policy that encourages the sector to thrive and grow, not one that saddles them with ever higher tax bills."

Food growers have hit out at the Government’s failures to ease inheritance tax on agricultural property following their outcries.

From April, farmers and small business owners who are married, are in a civil partnership or have deceased spouses, will be able transfer their inheritance tax allowance of up to £1million of full relief to each other if one of them dies without having used their allowance.

The change means a farmer could leave their £1million allowance to their partner, and use their own £1million allowance, to pass on £2million of farmland to their children without paying inheritance tax.

Tom Bradshaw, president of the National Farmers Union, said: “There’s been a small amendment within the Budget on the inheritance tax proposals, which means that the spousal allowance can be transferred and that is backdated to enable those who have already lost a spouse to make use of that spousal allowance.

“So [farmers] will be eligible for up to £2 million once you bring in that allowance. But it’s a really, really small change. It does not remove the human pressure, which is so intolerable for that older element of our community, and those that are terminally ill. It’s still an evil policy which has them trapped with no way to plan and we will continue to fight the policy.”

The Daily Express has demanded Ms Reeves scrap her inheritance tax changes through the Save Britain's Family Farms crusade.

Meanwhile two farmers were arrested, and a tractor seized by police, after the Met imposed restrictions on a planned protest against the family farm tax against the Autumn Budget. Both farmers have been released on bail.

But Reform UK’s deputy leader said the pair had been “treated like dangerous criminals”.

He added: “The decision to ban farmers from Whitehall was a national disgrace perpetrated by the Metropolitan Police and this Labour government. Peaceful farmers, exercising their democratic right to protest, were treated like dangerous criminals.

“Yet the same police happily waved through anti-Jewish hate marches in Whitehall, even on the day of the shocking synagogue attack in Manchester.

“I’m proud that Reform UK stepped in to provide legal support to these decent men and women who were unjustly arrested for daring to defend Britain’s rural communities.”

Farmer Clive Bailye said: “We were told the ban was because we would disturb local residents but the only two people who live on that street are the Prime Minister and Rachel Reeves.”

It is understood both farmers were released on bail.

A spokesman for the Met Police said that: “Conditions were put in place to prevent protestors bringing vehicles, including tractors and other vehicles to the protest.”

They added: “The vast majority of protestors complied with these conditions, however there were two arrests for breach of conditions and one tractor was seized for causing an obstruction.”