MPs will have the power to block a post-Brexit trade deal with the US if they believe it will damage animal welfare standards, Michael Gove says.

The Environment Secretary vowed to argue against any agreement that would open the door to chlorine-soaked chickens, for example – insisting he had Cabinet support.

But Mr Gove pledged that, regardless, Parliament – not the Government – would decide whether to plough ahead with a US deal, the dream of Tory hard Brexit supporters.

“I think if Parliament wanted to, it could stop the Government signing a trade deal,” he told the Commons environment select committee.

Mr Gove insisted chlorine-washed chickens were “perfectly safe to eat” – but suggested the way they were reared is “crueller”

“In America they cannot guarantee the same high standards in terms of how chickens are reared that we insist on here,” he told MPs.

“Unless there is a change in the American side we would say that those animal welfare rules are things on which we will not compromise.

“The whole point about trade deals is that you have got to be assertive in defence of your own interests.”

The Environment Secretary was also asked how the Government would achieve its hopes for “frictionless trade” in Ireland, to avoid a hard land border.

Neil Parish, the committee’s Conservative chairman, urged him to set out how the work was progressing, warning “otherwise this frictionless border is not going to work”.

“If we are outside the customs union, how are we going to get those lorries in and out with food that will go off?” he asked.

But Mr Gove was only able to say that ministers held “weekly meetings”, at which they discussed a “range of scenarios”.

In the Brexit negotiations, Theresa May agreed to “full alignment” of regulations needed to avoid a hard border, if no technological solution can be found, to apply across the UK.

Mr Gove denied that meant “full harmonisation”, arguing it was an “agreement to achieve the same goals by different means”.

Later, asked about the Cabinet debate on what sort of Brexit the Government will aim for after a transitional period, he claimed there was “absolute full alignment”.

Earlier this year, Trade Secretary Liam Fox appeared to open up a Cabinet split when he dismissed protests that US farmers use chemical washes to make up for inadequate hygiene on farms and abattoirs.