THE anti-Brexit campaign has just seven weeks to succeed - or Britain will be out of the EU for ever, Tony Blair admitted today.
The ex-PM confessed that any bid for the UK to rejoin the EU after leaving will be doomed.
But he insisted there is still time for Brexit wreckers to secure a second referendum which could overturn the 2016 vote.
Mr Blair is one of the leaders of the "People's Vote" campaign which aims to keep Britain in the EU.
But today he shot down the hopes of followers who believe the UK could quit the bloc then vote to rejoin in the near future.
He told Sky News: "Some people think you can leave on March 29, then you go into a long transition period, maybe try and rejoin during that period.
"I think that's highly unlikely - I think what will happen once you leave is you're out, and that will be it for a generation at least."
Once you leave, you're out for a generation
Tony Blair
Mr Blair claimed that a second referendum is now needed because the possible outcomes of Brexit have become clear.
He said: "I've never thought that you would get to another referendum going directly to it - you'll get to it when people see what the true Brexit alternatives are.
"And the truth is there are two. You can have a soft Brexit, which is really what Jeremy Corbyn is suggesting, or you can have the hard Brexit that Boris Johnson and Nigel Farage and other people want."
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Labour bosses have hinted they could back a rerun of the 2016 referendum if their efforts to force a soft Brexit fail.
But today Shadow Health Secretary Jon Ashworth admitted a second Brexit vote is "looking unlikely".
MPs will this week vote on the future path of Brexit - and could vote to wreck the Government's strategy by ruling out No Deal.
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