A motion expected to be approved by the party's annual conference on Monday promises that a Labour government would “extend equal rights to vote to all UK residents. If passed, the text would become official party policy.
The change would extend the right to vote in general elections to anyone with residency rights in the UK, regardless of their nationality. Currently only British, Irish and Commonwealth citizens are allowed to vote in general elections. Other foreign nationals living in Britain can vote only in local elections and European elections.
The proposal will be debated at the Labour conference in Brighton after being quietly included in a motion that says a Labour government should "maintain and extend" freedom of movement even if Britain leaves the EU, including by opposing any new immigration system based on migrants' income or skills.
The text says that, if Labour wins the next election, it will "extend equal rights to vote to all UK residents".
It also says that a Labour government would "close all detention centres" and "scrap all Hostile Environment measures", including restrictions on migrants' access to the NHS and welfare payments.
Extending the voting franchise would likely have a major impact if it was implemented before any second Brexit referendum and applied to the subsequent poll, with the 3 million EU citizens living in the UK easily enough to swing any vote heavily towards Remain. In the 2016 referendum, only people with the right to vote in UK general elections were allowed to vote.
It would also be likely to deliver millions more votes for pro-EU and pro-immigration parties in future general elections.
The move has been co-ordinated by the Labour Campaign for Free Movement and is expected to be approved by conference delegates when it is put to a vote on Monday.
A statement accompanying the motion, signed by Labour MPs, trade unionists and representatives of EU citizens in the UK, said it was "fundamentally wrong" that millions of people living in the UK are currently denied the right to vote.
It said: "Labour must be the champion of migrants’ rights in British politics. We must not allow working class people to be divided on the basis of where they are from.
"But speaking out on behalf of migrants is not enough. As representatives and activists of the labour movement, we understand that people only ever win justice and beat prejudice when they have a voice of their own. At minimum, this means having the right to vote."
It added: “Millions of people who have made their home here cannot vote here. It is fundamentally wrong that so many millions of people are denied a vote in decisions which affect them deeply.
“So at this Labour Party conference and beyond, we will support moves to extend equal rights to vote to all UK residents. And we will support moves to put this extension of the franchise into Labour’s next general election manifesto."
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