THE Scottish nation will soon be “crying out” for a second independence referendum because of the “horrors” of Brexit, the SNP’s constitution spokesperson has said.

Pete Wishart, the SNP’s longest serving MP, also told a conference fringe that his party should “respond positively” to the idea of a federal UK as a staging post to independence.

The Perth and North Perthshire MP said the SNP had to craft a new, more economically persuasive case for independence over the next few years in readiness for another vote.

He said: “We will be having another independence referendum.

“Not because we want it, but because the Scottish nation will be crying out for it as they start to experience the horrors of Brexit.

“They will be coming to the Scottish National Party saying, ‘For goodness sake, get us out of this mess.’

“So what we’ve got to be ready for, as we go forward, is to have the best possible position, the soundest arguments, that properly suggest where Scotland is economically.”

“We have to start thinking about how this pretty soon because Brexit could collapse in two years’ time,.

"We could be leaving without any deal, with the EU just thoroughly bored with the whining UK and their delusional nonsense and useless demands.”

Mr Wishart also said the SNP had to “respond nimbly” to suggestions of a more federal UK from other parties.

He said under Labour’s plan was for federal regions in England, meaning “Scotland would be of equivalence to East Anglia-stan or the Midlands” and it would never work.

However he said: “I think that we should respond positively to some real federalism as it goes through the United Kingdom because it moves us on in the constitutional debate.

“It doesn’t deliver us where we want to be as an independent nation, but it moves us significantly forward.

“Because what we would have is full fiscal autonomy, in charge of all our resources, in charge of all the raising of tax and spending it within our own parliament, so it’s a good thing.”

Earlier, Ms Sturgeon told BBC Radio Scotland it remained SNP policy for Scotland to join the EU as a full member if there was a vote for independence.

However she said it would be “premature” to set a date for a second referendum given the uncertainty around Brexit.

She said: “That doesn't mean we shouldn't make the case for independence, build that case and strengthen that case.

"Because increasingly the UK right now is engulfed in chaos, we are seeing a developing disaster, in my view, with the Brexit negotiations.

"And the case for Scotland taking control of our own future, having the decisions that shape our future in our own hands, in my view gets stronger by the day".

Tory MP Ross Thomson said: “Not only does Sturgeon want to ride roughshod over the vote to stay in UK, she also wants to overrule the UK vote to leave the EU. Her plan is to leave the UK, hand our sovereignty over to Brussels and, in so doing, build a border at Berwick.

“It seems the SNP are simply airbrushing the 1m Scottish Leave voters from history.”