Jo Swinson has described breaking up the United Kingdom, if Scotland was to vote for independence, as "much more difficult than what we're experiencing with Brexit".

The Liberal Democrat leader said it is a lesson she has learned throughout the process of Britain's decision to leave the European Union, which was made in June 2016.

Speaking on radio programme Scotland's Talk In on Clyde 2 and Forth 2, the East Dunbartonshire MP said she was the only party leader campaigning to keep Scotland in the UK and the UK in the EU.

Last week at the SNP's conference in Aberdeen, Scottish First Minister Nicola Sturgeon said a second independence referendum north of the border "must happen next year".

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But on Sunday Ms Swinson said: "I want the UK to stay in the European Union, that's what I'm working for and I believe that's still possible.

"I believe we can still do that and I'm not giving up on that cause because I think we're better off having Scotland in the UK and the UK in the EU.

"And let's remember that's also what Scotland has voted for - 55% voted to keep Scotland in the UK, 62% voted to keep the UK in the EU.

"I'm pretty much the only party leader in Scotland that's arguing for that position.

"We are seeing with this last three and a half years of Brexit chaos just how difficult it is when you have intertwined regulations, institutions, countries working together for 40 years in the case of Europe - how untangling that is complicated and difficult.

"And I just think, breaking up that union of 300 years will be so much more difficult than what we're experiencing with Brexit, that it's the lesson I take from that Brexit process."

The Liberal Democrat leader also reiterated her own candidacy for prime minister, and the view there is "a real opportunity to overtake Labour" for her party.

She said neither Boris Johnson nor Jeremy Corbyn were fit for 10 Downing Street, criticising the former of being untrustworthy "on a daily basis".

On the Labour leader she said he had been "absolutely useless" on Brexit, but also "he's somebody who has failed to tackle anti-Semitism within his party".

Ms Swinson was pushed further on Brexit, with one caller suggesting she held his and the votes of 17 million others "in contempt".

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She replied: "What I hope we can do as a country is have a debate and an engagement which recognises that people for good, genuine motivations, think there is a different way forward that is going to be right.

"It's not necessarily I know better than you, it's just I have come to a different conclusion than you. We disagree and it's OK to disagree.

"I think one of the challenges here has been that I think I have no confidence there is genuinely a majority in this country for any specific type of Brexit."

She added: "What I've seen over the last three years has been the people who voted for Brexit, and led the campaign in Parliament, unable to even agree amongst themselves about what Brexit should look like.

"If they can't even agree what Brexit should look like then how can we have confidence that any particular Brexit is what most people actually want us to do.

"And therefore all I think is, we need to make sure people can have that choice between this specific Brexit or staying in the EU.

"I've literally heard MPs say that if it was Theresa May's Brexit deal they would rather stay in the European Union, so if Theresa May's Brexit deal had been on the ballot paper in 2016 they would have rather voted to remain, and so we might have had a different result.

"Similarly, there's many others that say if it's a very hard Brexit or a no-deal Brexit that wouldn't involve us being in the single market, then they wouldn't have voted for that, because they voted on the basis they were told we would be in the single market.

"I think that's kind of where the challenge is. There wasn't a specific agreement of what it would mean and so now people have different views of what it should mean I think it has to go to the public."