Britain will leave the EU if Labour voters do not turn out to vote in the referendum, according to a letter signed by every living former Labour leader or acting leader of the party, but not the current incumbent, Jeremy Corbyn.

The letter warns that Brexit could lead to “a profound and permanent loss" for the UK and warns: “If Labour stays at home, Britain leaves.”

While the letter, signed by former prime ministers Tony Blair and Gordon Brown, ex-Labour leaders Neil Kinnock and Ed Miliband, and former acting leaders Harriet Harman and Margaret Beckett, says that they join with the current leadership in urging a Remain vote, the absence of Mr Corbyn’s signature may be read as an implicit criticism of the current leader’s approach to the EU referendum campaign.

What has the EU ever done for us? Show all 7 1 /7 What has the EU ever done for us? What has the EU ever done for us? 1. It gives you freedom to live, work and retire anywhere in Europe As a member of the EU, UK citizens benefit from freedom of movement across the continent. Considered one of the so-called four pillars of the European Union, this freedom allows all EU citizens to live, work and travel in other member states. What has the EU ever done for us? 2. It sustains millions of jobs A report by the Centre for Economics and Business Research, released in October 2015, suggested 3.1 million British jobs were linked to the UK’s exports to the EU. What has the EU ever done for us? 3. Your holiday is much easier - and safer Freedom to travel is one of the most exercised benefits of EU membership, with Britons having made 31 million visits to the EU in 2014 alone. But a lot of the benefits of being an EU citizen are either taken for granted or go unnoticed. What has the EU ever done for us? 4. It means you're less likely to get ripped off Consumer protection is a key benefit of the EU’s single market, and ensures members of the British public receive equal consumer rights when shopping anywhere in Europe. What has the EU ever done for us? 5. It offers greater protection from terrorists, paedophiles, people traffickers and cyber-crime Another example of a lesser-known advantage of EU membership is the benefit of cross-country coordination and cooperation in the fight against crime. What has the EU ever done for us? 6. Our businesses depend on it According to 71% of all members of the Confederation of British Influence (CBI), and 67 per cent of small and medium-sized enterprises (SMEs), the EU has had an overall positive impact on their business. What has the EU ever done for us? 7. We have greater influence Robin Niblett, Director of think-tank Chatham House, stated in a report published last year: “For a mid-sized country like the UK, which will never again be economically dominant either globally or regionally, and whose diplomatic and military resources are declining in relative terms, being a major player in a strong regional institution can offer a critical lever for international influence.

A longstanding critic of the EU before he became leader, Mr Corbyn has been accused of being too tentative in his backing for a Remain vote.

In a major speech this week he said there was an “overwhelming case” for staying in, but focused his message on the dangers of a Conservative government renegotiating Britain’s relationship with the EU, and argued for "remain – and reform" in Europe.

By contrast, the ex-leaders' letter, published in The Guardian, offers a warm endorsement of the EU’s role in British life: “Labour’s values are inherent to Europe’s virtues," it says.

Corbyn slams referendum 'hype'

"Europe protects people at work; stimulates jobs and innovation; keeps prices lower; leads global action against climate change; makes us safer against terrorism; and magnifies Britain’s voice and values in the world.”

Like Mr Corbyn, the former leaders warn of the risk of “an emboldened right wing” of the Conservative party in the event of a Brexit vote, but goes on to offer a strongly worded warning about the long-term impact of leaving the EU.