Theresa May has defeated a rebel Tory move which could have forced her to keep Britain in a customs union with the EU.

The Prime Minister was saved from a humiliating reverse after MPs backed the government by a margin of just six votes, rejecting the amendment by 307-301.

Labour Brexiteers Frank Field, Kate Hoey, John Mann and Graham Stringer – along with independent Kelvin Hopkins – voted with the Government.

MPs in the House of Commons read out the results of the vote where MPs have defeated a Tory backbench Trade Bill amendment linked to the customs union by 307 votes to 301, majority six. PRESS ASSOCIATION Photo. Picture date: Tuesday July 17, 2018. See PA story POLITICS Brexit. Photo credit should read: PA Wire
MPs in the House of Commons read out the results of the vote where MPs defeated a Tory backbench Trade Bill amendment to keep Britain in the EU customs union by 307 votes to 301 (Picture: PA)

But 12 Conservatives – Guto Bebb, Heidi Allen, Kenneth Clarke, Jonathan Djanogly, Dominic Grieve, Stephen Hammond, Phillip Lee, Nicky Morgan, Bob Neill, Antoinette Sandbach, Anna Soubry and Sarah Wollaston – broke ranks to back the customs union measure.

Mrs May was defeated on a separate amendment to her flagship Trade Bill, which will require her to seek continued UK participation in the EU’s system for regulation of medicines after Brexit by 305 votes to 301.

A senior minister said it was ‘extraordinary that we lost the vote that didn’t matter and won the one that did’.

But added: ‘I don’t know where we go from here.’

International Trade Secretary Liam Fox addressing MPs during the third reading of the Trade Bill in the House of Commons, London. PRESS ASSOCIATION Photo. Picture date: Tuesday July 17, 2018. See PA story POLITICS Brexit. Photo credit should read: PA Wire
International Trade Secretary Liam Fox addresses MPs during the third reading of the Trade Bill in the House of Commons (Picture: PA Wire)

The unsucessful amendment would have forced the Government to adopt a negotiating objective of seeking to keep the UK in ‘a customs union’ with the EU after Brexit, unless it has managed to negotiate a ‘frictionless free trade area for goods’ by January 21 next year.

Downing Street insisted this would have breached Mrs May’s red line to take Britain out of the customs union.

But former transport minister Mr Hammond insisted its provisions were ‘entirely in line’ with Mrs May’s Brexit White Paper.

The successful amendment requires Mrs May to make it an objective in negotiations with Brussels to ensure that the UK can continue to participate in the regulatory network operated by the European Medicines Agency.

The Trade Bill later passed its third reading by a margin of 317 to 286 and will go on to the House of Lords.

MPs in the House of Commons read out the results of the vote after the Tory backbench amendment linked to medicines, new clause 17, was approved by 305 votes to 301 - a majority of four, which marked the Government's first defeat on the Trade Bill. PRESS ASSOCIATION Photo. Picture date: Tuesday July 17, 2018. See PA story POLITICS Brexit. Photo credit should read: PA Wire
MPs in the House of Commons read out the results of the vote after new clause 17 was approved by 305 votes to 301 (Picture: PA)

International Trade Secretary Liam Fox said the legislation would be ‘the confident first step that the UK takes towards establishing itself as an independent trading nation for the first time in over 40 years’.

But his Labour shadow Barry Gardiner said: ‘The Government’s handling of Brexit over the past week has been an utter shambles. We have a Prime Minister who is in office, but not in power.’

Pro-EU Labour MP Chuka Umunna hit out at Labour Brexiteers who opposed the customs union amendment, saying: ‘It’s very disappointing and our communities will question why Labour MPs are jeopardising jobs.’

Green Party co-leader Caroline Lucas, a leading supporter of the People’s Vote campaign for a second referendum, said Brexit had ‘sunk further into the Westminster quagmire’.

Britain's Prime Minister Theresa May walks to deliver a speech as she opens the Farnborough Airshow, south west of London, on July 16, 2018. Britain sought to project an image of aerospace prowess long after it leaves the European Union, at the Farnborough airshow on Monday, as Airbus and Boeing announced a raft of deals and issued optimistic outlooks for the global industry. / Getty Images / POOL / Matt CardyMATT CARDY/AFP/Getty Images
Theresa May survived the significant challenge to her Brexit plans (Picture: Matt Cardy/AFP/Getty Images)

And Liberal Democrat Brexit spokesman Tom Brake said Mrs May’s Chequers negotiating strategy was now ‘in tatters’.

‘The passing of this deeply flawed bill can’t mask the profound splits at the heart of the Tory party,’ said Mr Brake.

A government spokesman said: ‘As set out in the White Paper, the UK is seeking participation in the European Medicines Agency.

‘We would look to be an active participant and this would involve making an appropriate financial contribution. We will now reflect on this amendment and seek to revisit in the Lords.’

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