Last week Jeremy Corbyn gave a speech that for days beforehand had been touted as a dramatic shift in the Labour party’s position on Brexit. Not surprising for us Lib Dems, but sadly pro-Europeans hoping for a chink of light got nothing of the sort. Mr Corbyn’s pledge to try to negotiate a new UK-EU customs union amounts to a costly and pointless exercise, which will put the UK in a lesser position than it enjoys currently inside the EU customs union.

Labour has shown it would take the same unrealistic cherrypicking approach we have seen from the Tory government. The idea that we can retain the benefits of access to the single market and the customs union without accepting the four freedoms, of which free movement is one and Labour’s general election manifesto opposed, is a complete non-starter from the EU’s perspective. It is galling that at this stage of the negotiations, neither Labour nor the Tories have any grasp of what is feasible.

If pro-EU voters want their voices to be heard, there is only one choice at the local elections. Only the Liberal Democrats have unequivocally stood up for the rights of EU citizens from the start. Only we believe our EU membership is already the best possible deal we can have. Only we have consistently supported staying inside the single market and customs union through key votes and amendments in parliament. Only we have promised the people a final say on the government’s Brexit deal. On 3 May voters across London will have a great opportunity to send a message to both Labour and the Tories that their stance simply isn’t good enough, by voting for the Liberal Democrats instead.

Vince Cable Leader, Liberal Democrats and MP for Twickenham, Tom Brake Liberal Democrat spokesperson on exiting the European Union and International Trade, and MP for Carshalton and Wallington, Ed Davey Liberal Democrat spokesperson on home affairs and MP for Kingston & Surbiton, Caroline Pidgeon Liberal Democrat London assembly member and 108 Liberal Democrat council candidates from across London

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• This letter was amended on 6 March 2018 to include the reference to 108 Liberal Democrat council candidates across London as signatories.

