Labour MPs want to force a vote to let Parliament decide if Britain leaves the single market

Exclusive: Several former shadow ministers among group seeking to delay Article 50 until a second parliamentary vote is held

Chuka Umunna has backed the amendment seeking a separate parliamentary vote on the single market (AFP)

Labour MPs are to try to force a vote giving Parliament the right to decide whether Britain should stay in the EU single market – and are demanding Theresa May delays triggering Article 50 until such a poll is held.

In an amendment tabled to the Withdrawal from the European Bill, 10 Labour backbenchers, including a number of former shadow cabinet ministers, demand the Prime Minister holds off on formally beginning Brexit negotiations until Parliament “has determined whether the UK should also seek to withdraw from the European Economic Area” – the official name for the single market.

Ms May has previously said she plans to take UK out of the single market, arguing that staying in “would mean not leaving the EU at all”.

The amendment was tabled by Wes Streeting, the MP for Ilford North and a member of the Treasury Select Committee, and backed by senior Labour MPs including Chuka Umunna, the former shadow Business Secretary, Heidi Alexander, who was previously shadow Health Secretary, and Maria Eagle, who has held several posts in Jeremy Corbyn’s top team.

It seeks to force a vote on membership of the single market that would be held separately to the vote, forced upon the Government by last week’s Supreme Court ruling, on whether Theresa May should trigger Article 50.

The amendment states: “The Prime Minister may not give the notification at section (1) until such time as Parliament has determined whether the UK should also seek to withdraw from the European Economic Area in accordance with Article 127 of the EEA.”

Should the Government decide to reject the amendment, it could lead to further accusations that ministers are undermining the role of Parliament in determining how Brexit proceeds.

Downing Street wants MPs and peers to pass the Bill as swiftly as possible and without conditions being added that would bind the Prime Minister’s hands in negotiations with the EU.

After tabling the amendment, Mr Streeting told The Independent: “Throughout the referendum campaign prominent members of the Leave campaign gave assurances that leaving the EU would not mean leaving the single market. The Conservative manifesto committed to keeping us in the single market.

“In the absence of a mandate to quit the single market, the Government must now allow Parliament to decide our future trading relationship with the EU.

“I am firmly of the view that membership of a single market of half a billion customers represents the best possible trading relationship with our nearest neighbours, a better deal than we would get from other nations and certainly more preferable than lengthy trade negotiations with the EU that could take up to a decade. Jobs and livelihoods are riding on this.”

Theresa May has previously argued the UK “cannot possibly” remain in the EU. In a speech earlier this month she said: “I want to be clear: what I am proposing cannot mean membership of the single market.

“It would, to all intents and purposes, mean not leaving the EU at all.

“That is why both sides in the referendum campaign made it clear that a vote to leave the EU would be a vote to leave the single market.”

The issue is set to be raised by MPs as Parliament begins debating the Government’s Brexit bill this week.

In other amendments, tabled in the name of Jeremy Corbyn, Labour is demanding Parliament is given regular updates on Brexit negotiations and that the UK’s devolved assemblies are also consulted. The party has also said it will seek to ensure the UK gets “tariff-free” access to the single market, with shadow ministers having suggested the party could withdraw its support for the bill if these conditions are not met.

Another group of Labour backbenchers, led by former leadership contender Owen Smith, is also demanding the vote on Article 50 is delayed until ministers have published a full White Paper laying out their plan for negotiations.