The Ashford MP and effective Deputy Prime Minister Damian Green says it is vital the UK makes a success of Brexit to protect jobs and the economy.
But a South East Conservative MEP has fired a broadside at the government to say that it has no mandate for a “hard” Brexit following the election.
Richard Ashworth issued a blunt warning that the Brexit could harm the UK economy.
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“Given (Theresa May) has no overall majority, she has to get on and run the country in the best of interests of everybody. I do not think she has a mandate for the “hard” Brexit she described.”
He added that a “complete severance” from the world’s largest and wealthiest market on the UK’s doorstep would be “economic suicide”.
He continued: “No one has been able to convince me why global Britain is going to flourish while at the same time we are going to be offered border free, tariff free and seamless trading arrangements with the 27 member states.
“What is true is that Brexit would bring a significant fall in the value of sterling.”
That was not good for the UK as it imported more than it exported, he said.
The first round of landmark talks got underway today as David Davis met the EU chief negotiator Michel Barnier in Brussels to discuss the terms of the UK’s departure.
The PM has stood by her insistence that “no deal would be better than a bad deal”.
Mr Green, recently promoted to First Secretary of State, said the cabinet would put aside their personal differences over whether to stay or go in the wider interests of the country.
“There are people in the cabinet who argued passionately on both sides of the referendum debate last year but the thing that unites us is that we need to move on," he said.
“We have had that debate; the country has decided. What we now need to do is get the best deal we can so we can continue the successful trading relationships we have, while taking the opportunities of other trading relationships that emerge around the world.”
It comes as businesses set out their wish-list from Brexit and called on the government to consult them during the negotiations.
The business wish-list has been signed by the bosses of the British Chambers of Commerce, CBI, Institute of Directors, Federation of Small Businesses and the EEF.
It includes tariff-free trade between the UK and Europe – and asks for the business community to be consulted throughout the negotiations.
Mr Green said the protection of UK citizens in Europe was a priority in any Brexit deal.
“We want to protect the interests of British citizens abroad and European citizens here, so there are a huge number of big issues.
“There’s a lot to do but whatever side we took on the referendum the cabinet is united on getting that best deal.”