Sir Vince Cable will liken the Liberal Democrats’ campaign to stop Brexit to Charles Kennedy's opposition to the Iraq war as he launches the party’s EU election campaign.
The Lib Dem leader and Twickenham MP is to say that only his party have the determined army of volunteers standing against the UK’s withdrawal from the bloc.
He will say it should be remembered that the Lib Dems had been against Brexit from the start, even though they stood alone.
Sir Vince is to say: "Without the Liberal Democrats, the campaign to stop Brexit wouldn't have got off the ground. We are proud to work across party lines to stop Brexit but it bears remembering that when we started, we stood alone.
"In Parliament, it reminded me of Charles Kennedy's opposition to the Iraq war. We were barracked on all sides but we stood steadfast anyway. As with that tragedy, millions have now come round to our point of view and a clear majority of the public now supports a People's Vote."
Sir Vince, who last month said he will step down in May, will say the Brexit negotiations have been "a national humiliation" over the past three years as "promise after promise of the Leave campaign has been found wanting".
The European elections were just the latest sign of Brexiteers' "dismal failure... to have any common plan about what Brexit should mean", he will add.
Jeremy Corbyn was involved in a "stitch-up with the Conservative Government", and "no wonder Labour supporters feel so let down", the party leader will say.
Urging Remainers to vote for the Liberal Democrats, Sir Vince will say: "What we know is that any form of Brexit puts our country at risk - the NHS, our public services, jobs across the country and peace in Northern Ireland.
"Our global reputation has taken a battering for a project which would leave us worse off at home and less influential in the world.
"Our ambition is no less than to stop Brexit, and see this new group of Liberal Democrat MEPs influence the future of Europe for years to come."
It comes after Nigel Farage's pledged to use next month's European Parliament elections as a "springboard" to take the party into power in Westminster.
The former Ukip leader’s new Brexit Party is planning to run candidates in the next General Election, the Leave campaigner also revealed.
In an interview with The Sun on Thursday, Mr Farage said: "We want the European election to be the first step of a massive change that resteps entirely British politics and actually makes it look more like the country.
"MPs will realise that if they carry on trying to stop Brexit, they'll lose their seats at the next General Election. I think they will be very fearful of what the Brexit Party can do to them.
"That'll give them two choices - either they change and start to deliver Brexit, or we'll replace them at that General Election.”