The minister for defence procurement resigned on Monday to vote against the government on amendments to its Brexit customs bill.
Guto Bebb, who had been in the role since January, stepped down ahead of the controversial votes, two of which the government eventually won with a majority of just three.
A replacement has not yet been announced. The Farnborough Airshow, the UK’s biggest defence and civil airshow, continues until the end of the week.
Bebb, MP for Aberconwy and a vocal critic of Eurosceptic MPs in recent weeks, told the BBC he felt “duty bound” to resign in the face of what he saw as the government caving in to hard Brexiteers.
Last month he came out in support of businesses and lashed out at then health secretary Jeremy Hunt for criticising Airbus’ threat to leave the UK. He said: “The dismissive attitudes shown towards our business community by senior Cabinet ministers is both unworthy and inflammatory.”
Bebb was a supporter of the prime minister’s Brexit plan drawn up at Chequers earlier this month, branding former foreign secretary Boris Johnson “selfish” for resigning in opposition to the agreement.
But amendments by the pro-Brexit Conservative European Research Group (ERG) on Monday, accepted by the government, were made “with a simple intention of damaging the Chequers agreement,” he said.
“I think the ERG amendments [on Monday] have absolutely undermined the negotiating position that the prime minister had and I felt duty bound to try and vote to highlight the fact that the Conservative Party should be led by the prime minister not by the leadership of the ERG group.
“I'm disappointed that that point wasn't made last night with a victory in the vote in question.”
A spokesperson for 10 Downing Street said a replacement hadn’t been chosen yet, “but that will be announced imminently”.
“We thank him for his service at the Ministry for Defence and the Wales Office as well. The PM has expressed her thanks to him.”
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