THE Liberal Democrats have put stopping Brexit at the heart of their General Election platform as they sought to underline their claim to be the party of Remain.

The party's manifesto, published on Wednesday, holds out the prospect of a £50 billion "Remain bonus" to be spent on public services and tackling inequalities if they succeed in keeping Britain in the EU.

It sets out plans to tackle the climate change "emergency" through generating 80% of the country's electricity through renewables by 2030, provide free childcare from the age of nine months, and recruit 20,000 more teachers.

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Lib Dem leader Jo Swinson said: "This manifesto is a bold plan to build a brighter future for our country, and that starts with stopping Brexit.

"Labour and the Conservatives can't offer the country a brighter future because they both want Brexit. We know that will be bad for our economy, bad for our NHS and bad for our environment.

"Our politics has been dominated by the two, tired old parties for too long. This election provides an opportunity to change the future of our country and build a brighter future with the Liberal Democrats."

The manifesto reaffirms the party's commitment to end the Brexit process by revoking Article 50 if there is a majority Lib Dem government following the election on December 12.

If not, the manifesto says they would continue to campaign for a "people's vote" in a fresh referendum with an option to stay in the EU on the ballot paper.

"The election of a Liberal Democrat majority government on a clear stop Brexit platform will provide a democratic mandate to stop this mess, revoke Article 50 and stay in the EU," the manifesto says.

"In other circumstances, we will continue to fight for a people's vote with the option to stay in the EU, and in that vote we would passionately campaign to keep the UK in the EU."

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The Lib Dems argue that staying in the EU would generate a £50 billion "Remain bonus" over five years, through higher levels of growth.

They estimate the economy will be 1.9% larger in 2024-25 than it would be under Boris Johnson's Brexit deal, giving them extra funding to spend on their priorities in the years ahead.

They include a target of doubling the amount of power generated through renewables by 2030 while investing £15 billion over five years in retro-fitting 26 million homes with insulation and zero-carbon heating.

The party says it would increase opportunities through providing 35 hours a week free childcare for all two to four year-olds - with the offer extended to those aged nine to 24 months where the parents are working.

At the same time the party says it would give all adults £10,000 to spend on skills and training throughout their lives through the creation of a new "skills wallet".

The manifesto promises to reverse frontline budget cuts for schools in England since 2105 with an emergency cash injection of £4.6 billion next year.

It says that by 2024/25, they will be spending £10.6 billion more on schools than is currently being spent - enabling them to increase the number of teachers by 20,000 over five years.

The party is also promising that mental health services would be treated with the same urgency as physical health with a £11 billion cash injection over the lifetime of the parliament.