Theresa May has no grounds for saying that "no deal is better than a bad deal" when Britain leaves the European Union, an influential committee of MPs said today.
But the Commons Brexit committee was divided, with six Eurosceptic members, including the former cabinet minister John Whittingdale, refusing to endorse its report.
Dominic Raab, the Conservative former justice minister, who voted against the report, said the split would undermine the "credibility and influence" of the committee, which was established to hold the government to account while it leads the country out of the EU.
The prime minister's hard negotiating stance is "unsubstantiated", the report on the government's Brexit negotiations concluded. Leaving without a deal would be the worst-case scenario and Whitehall departments should urgently put in place contingency plans to mitigate it.
Alistair Carmichael, a Liberal Democrat MP who sits on the committee (and who supported remaining in the EU), said the report was a "devastating critique of the shambles that is the Conservative Brexit strategy".
However, six of the 21 members of the committee – five Conservatives and the Democratic Unionist Sammy Wilson – voted against the report.
"The report was rushed, skewed and partisan," Raab said. "After two reports that had strong support, it's regrettable that this one split the committee. That undermines its credibility and influence, but I hope and expect the committee will learn the right lessons, as we move forward."
Hilary Benn, the chairman, told Today on BBC Radio 4 he was disappointed some of the committee disagreed with the conclusions, but said the report was fair and balanced. The dissenters were outnumbered by 10 MPs who voted in favour of the report. Some abstained, including Michael Gove, the former education secretary and prominent Brexit campaigner.
In January, in a landmark speech setting out her negotiating objectives for Brexit, May said she will push for a close economic relationship with Europe, including a comprehensive free-trade deal – but would rather walk away without any agreement rather than submit to onerous terms if the other 27 member states try to play hardball with the UK.
"No deal for Britain is better than a bad deal for Britain," the prime minister said, because the UK could strike new trading arrangements with non-European countries and lower taxes to attract businesses. However, MPs have expressed concerns about that stance.
Last month, the foreign affairs committee said failure to reach a deal would result in "mutually assured damage" to both the UK and EU. And the chance of Britain not getting a deal was very real, given the tight time-frame in which a new agreement has to be negotiated.
Its conclusion was seconded by the Commons Brexit committee in its new report.
The committee called for Whitehall to conduct an urgent assessment of the consequences of crashing out without a deal, and for the government to publish its contingency plans.
In testimony to the committee last month, Brexit secretary David Davis said failing to reach an agreement "is not as frightening as some people think, but it is not as simple as some people think".
Some contingency planning was underway, Davis said. But he also told the committee there had not been an assessment of the economic cost of Britain withdrawing from the EU without a new deal in place since the referendum.
In its report, the committee said: "Without an economic assessment of 'no deal' having been done and without evidence that steps are being taken to mitigate what would be the damaging effect of such an outcome, the Government's assertion that 'no deal is better than a bad deal' is unsubstantiated."
The 130-page report cast doubt on whether a wide-ranging free-trade agreement – May's preferred outcome – can be achieved in only two years. " There is no precedent for the conclusion of a major, comprehensive bilateral or multilateral FTA covering goods and services within two years," it said, though it noted that Britain's legal and regulatory systems are already closely aligned, which could accelerate the process.
Numerous other uncertainties hang over the Brexit negotiations, according to the report, including the continued availability of funding for scientific research, the openness of the Irish border, and cooperation on cross-border crime-fighting.
In a statement in response to the report, Davis said: "We have been absolutely clear that we are seeking a deep and special partnership with the EU, taking in trade and the many other areas where we have shared aims and values, such as security.
"We are confident that such an outcome is in the interests of both sides. However, a responsible government should prepare for all potential outcomes, including the unlikely scenario in which no mutually satisfactory agreement can be reached, and that is exactly what we are doing.
"We have also been analysing the impact of different scenarios on different sectors of the economy."
This post has been updated to reflect the division on the committee.
Alex Spence is a senior political correspondent for BuzzFeed News and is based in London.
Contact Alex Spence at firstname.lastname@example.org.
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