FOLLOWING the proposed "Plan B" route to independence, could see Scotland in "the sort of hellish limbo currently endured by the people of Catalonia", according to SNP MP Pete Wishart.

Wishart, who represents Perth and North Perthshire, called for clarity on the plan that would avoid a Westminster veto and achieve independence for Scotland. He also agreed that the proposal should be "put to bed" with a debate at the SNP conference.

Last year Chris McEleny, the SNP Leader on Inverclyde Council, and Western Isles MP Angus MacNeil unsuccessfully tried to have a debate on this idea – which they billed as "Plan B" – added to the agenda at the party's conference.

It would have allowed members to discuss if a pro-independence majority in Scotland at either a Holyrood or Westminster election could be a mandate to open negotiations with the UK.

It would also pile on the pressure for the Prime Minister to grant a Section 30 order, thereby transferring powers over to Holyrood in order to hold a vote.

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"My little bit of advice to my good friends in the ‘Plan B movement’ is to at least come up with some sort of concrete proposal so we can have some idea what it is we are supposed to debate," Wishart wrote on his blog.

He warned of the dangers of holding an independence referendum whether Scotland has permission from Westminster or not, adding: "‘Just doing it anyway’ means we would be doing something broadly similar to what Catalonia did when they ‘won’ their uncontested referendum – without actually winning a referendum! This would in effect mean we would be declaring some sort of Unilateral Declaration of Independence (UDI).

"The consequences of that could not be more serious. Almost certain to be one of the first things to happen is that we would have all of this immediately ruled illegal and be disenfranchised from the entire international community. We would be left in the sort of hellish limbo currently endured by the people of Catalonia."

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Wishart also argued that there is a good chance the SNP will secure a majority at the 2021 Holyrood elections, allowing negotiations on "Plan B" to begin.

He added: "That would therefore mean that the 2021 election ceases to be a General Election in the conventional sense and instead becomes a single issue plebiscite exclusively on the proposition that if the SNP secures a majority we move towards becoming an independent state. If it was to happen there would be no programme for Government, no defence of a record in power, just a straight forward one issue independence question."

Wishart concluded by saying that the time for Plan B "has not come yet".

"What always surprises me is that so many people think that ‘No’ is immutable and just so readily accept it," he continued. "But they will be overcome and that will be done by force of electoral numbers, and if necessary, an escalation of tactics by getting all our indy strategy ducks in a row. There may be a time for some sort of Plan B, but that time has not come yet."

Replying to McEleny on Twitter after he had shared the blog post, Wishart called for a debate to be held at conference.