The minister for universities and science has resigned in protest over Theresa May’s Brexit deal, calling it “naive”.
Sam Gyimah, who has been tipped as a future leader for the Tory party, said any deal struck with Brussels will be “EU first”.
Writing on his Facebook, the East Surrey MP said: “After careful consideration and reflection, I cannot support the government’s deal and as such, I have tended my resignation as universities and science minister.”
Mr Gyimah, who campaigned for Remain but represents a Leave constituency, labelled negotiations over Galileo, the EU’s strategic satellite navigation system, “a foretaste of what’s to come under the government’s Brexit deal”.
He added: “Having surrendered our voice, our vote and our veto, we will have to rely on the ‘best endeavours’ of the EU to strike a final agreement that works in our national interest.
“As minister with the responsibility for space technology, I have seen first-hand the EU stack the deck against us time and time again, even while the ink was drying on the transition deal.
“Galileo is a clarion call that it will be ‘EU first’, and to think otherwise – whether you are a Leaver or Remainer – is at best incredibly naive.”
Mr Gyimah said Theresa May – who is in Argentina for the G20 summit – should not rule out a second referendum.
He conceded that Mrs May’s deal “has been hard won”, but says “at its heart, all the big decisions in the political declaration that will shape our future in Europe, and the world, are yet to be agreed”.
He added: “It is a deal in name only. And we will be relying on the good faith of the EU to deliver the bespoke deal we have been led to expect.”
The Oxford-educated MP argued in his statement the “sensible compromise Brexit deal” will leave the UK “poorer, less secure and weaker in the pursuit of our national interests”.
He suggested alternatives include a second referendum, saying: “We shouldn’t dismiss out of hand the idea of asking the people again what future they want, as we all now have a better understanding of the potential paths before us.”
He ended his statement with a compliment for the PM – before confirming that he is unable to back her any longer.
“The grit and determination demonstrated by the prime minister should be an inspiration to us all,” he said.
“I am saddened, as an early and vocal backer of her leadership, to have reached a cross-roads where I cannot support her on this crucial issue.”