A war of words over food standards has broken out after Liberal Democrats said Pembrokeshire's two MPs should “hang their heads in shame” for voting against measures to protect high environmental and animal welfare standards.

Conservative MPs Simon Hart and Stephen Crabb were among those who rejected amendments to the Agriculture Bill on Wednesday night which would have forced the UK Government to ensure that British food and animal welfare standards are maintained in any trade deals.

But Preseli Pembrokeshire MP Mr Crabb dismissed the criticism as 'pathetic' and said contentious products like chlorinated chicken and hormone-reared beef remain banned in the UK.

More than a million people signed an NFU petition calling for the UK Government to put laws in place that prevent imports of food that is produced in ways that are illegal here in the UK.

The Liberal Democrats have committed to continue the fight to protect British farmers, including exploring further amendments to the Trade Bill.

Liberal Democrat spokesperson Tina Roberts, for Preseli Pembrokeshire, said: “The Conservatives promised to protect British farmers, but they betrayed that promise.

“We now risk seeing foods that are currently illegal in the UK – like hormone treated beef, and fruit and vegetables produced using banned pesticide – making it onto our supermarket shelves."

But the claim was flatly contradicted by Mr Crabb.

“This is frankly pathetic from the Liberal Democrats. I have met and worked closely with the local farming unions to push for practical measures to support UK agriculture post-Brexit and I am pleased that they have welcomed what the Government is doing," he said.

“The new Trade and Agriculture Commission has already met with the Welsh farming unions along with MPs like myself who speak up for farming interests. I am pleased we were all on the same page when it comes to protecting high food standards. Products like chlorinated chicken and hormone-reared beef remain banned in the UK. There has been no weakening of any of our food standards.”

Carmarthen West and South Pembrokeshire MP Simon Hart, who is also Welsh Secretary, said he and Trade Secretary Liz Truss had spoken to the virtual NFU conference session yesterday and according to the NFU Cymru president they were “hugely encouraged”.

Alistair Cameron, Welsh Liberal Democrat Senedd candidate for Carmarthen West and South Pembrokeshire, added: “Simon Hart and Stephen Crabb should hang their heads in shame. They have let everyone across Carmarthen West and Pembrokeshire down by putting Boris Johnson’s government first.”

Welsh Liberal Democrat leader Jane Dodds said: “Unlike the Conservatives, Liberal Democrats back British farming. We want the Government to work in partnership with UK farmers to protect our world class food and animal welfare standards, cut greenhouse gas emissions and support the recovery of our natural environment.

“We will do everything we can to continue the fight to protect British farmers, including exploring further amendments to the Trade Bill.”