Farmers are “in it for the money” because they are “businesses that need to make a profit”, the Environment Secretary has said.

Steve Reed also accused the Conservatives of “posturing” while he took questions about farmer suicides and after Conservative shadow environment secretary Victoria Atkins said “not everyone will be able to celebrate Christmas” this year.

Liberal Democrat environment, food and rural affairs spokesman Tim Farron also said farmers are “genuinely devastated by the Government’s family farm tax”.

Earlier this year, the Government unveiled changes to the agricultural property relief, ending the 100% exemption from inheritance tax on qualifying business and agricultural assets worth more than £1 million.

Mr Reed told MPs: “The shadow secretary of state, as well as the former prime minister, keep telling farmers they’re not in it for the money. We know that they are.

“They’re businesses that need to make a profit, and our new deal for farmers, including increasing supply chain fairness is intended to make farms profitable and successful for the future, in a way that they were not under the previous government.”

Josh Fenton-Glynn, the Labour MP for Calder Valley, had earlier described an “increasingly unprofitable” agricultural sector which had been “undercut” by previous trade deals.

He had asked whether farmers in his West Yorkshire constituency would get their “fair share” from a new 25-year roadmap to make farming profitable again.

Mr Farron later told MPs: “Farming communities across the country are genuinely devastated by the Government’s family farm tax, which will affect many in my patch who are on less than the minimum wage.”

Mr Reed replied: “The vast majority of APR (Agricultural Property Relief) claimants will not pay anything. This Government, unlike the previous government that thought farmers were not in it for the money, wants them to succeed.

“So we’re embarking on a farming road-map and a new deal for farming that will look at supply chain fairness, stopping farmers being undercut in trade deals like the one they agreed with Australia and New Zealand.

“Our intention is to make farming profitable for the future, their record is 12,000 farming businesses that went bust.”

Ms Atkins said: “Not everyone will be able to celebrate Christmas. In recent weeks, a farmer took himself off to a remote part of his farm and killed himself. The message he left his family, who wish to remain anonymous, is that he did this because he feared becoming a financial burden to his family because of changes to inheritance tax.

“This is the human cost of the figures that the Secretary of State provides so casually. What does the Secretary of State say to that grieving family?”

Mr Reed said: “I send my heartfelt sympathies to that family but I think it is irresponsible in the extreme to seek to weaponise a personal tragedy of that kind in this way. Where there is mental ill health then there needs to be support for that, and this Government is investing in it.

“She knows from the last year for which data is available that the vast majority of claimants will pay absolutely nothing following the changes to APR.”

Following up, Ms Atkins called for farmer and landowner suicide data on a monthly basis “so that we – the House – and the outside community can understand the human costs”, as she labelled Mr Reed’s answer as “heartless”.

Mr Reed replied: “Mental health services are the responsibility of the National Heath Service and the former health secretary (Ms Atkins) – who broke the NHS – is in no position to lecture anybody about public services.

“She was no friend of the health services, no friend of the mental health services and she is no friend of farming.

“Twelve thousand farms went bust on their (the Conservatives’) watch. They failed to get £300,000 out of the doors and into the pockets and bank accounts of farmers, and they signed a trade deal with Australia that undercut British standards on environmental and welfare standards.

“I hear the posturing. It is this Government that is standing up for farming.”