The SNP is misleading people over an alternative Brexit plan, according to Scottish Secretary David Mundell.

Defending the Prime Minister from accusations she had lied about the temporary nature of the Brexit backstop plan, Mr Mundell said the only duplicity was coming from SNP Westminster leader Ian Blackford.

Mocking the dramatic SNP walkout from Westminster earlier this year, the Scottish Secretary said Mr Blackford's latest PMQs attack on Theresa May was using language to "draw attention to himself" in "another stunt".

READ MORE: MPs may be given vote on whether UK adopts Brexit backstop over Northern Ireland 

Mr Mundell said: "I think the Prime Minister has been very clear and very open throughout the process, and has not hidden the things within the deal that people might or might not like.

"She has not hidden that this is a hard decision, it's not a straightforward decision, but I also think she has been very clear about what the reality is if people don't support this deal.

READ MORE: Ian Blackford accuses Theresa May of 'perhaps inadvertently' misleading parliament over Brexit 

"I don't think anybody has been misled - if there is any attempt at misleading it is from the SNP who are somehow projecting they want some other, better alternative yet they're quite prepared to impose a no deal on Scotland."

First Minister Nicola Sturgeon met the leaders of all opposition Westminster parties last month in an attempt to thrash out an alternative plan that could achieve a Parliamentary majority but left London empty-handed.

HeraldScotland:

Mr Mundell explained he would be backing Mrs May's deal to avoid a no deal Brexit, because he believed there was no credible alternative available if MPs vote down the Government's plan next Tuesday.

"There are other people who believe, fancifully, there is some other deal out there in the ether and they just need to vote this deal down for it to materialise in their Christmas stocking," he said. "That is not going to happen.

"The deal that is one the table is the realistic option that's available.

"None of the other speculated options we can say at this moment are credibly with a chance of achieving majority support in Parliament."

But, following a speech to business leaders urging support for Mrs May's deal, Mr Mundell admitted he was not "totally comfortable" with the details around Northern Ireland.

The Scottish Secretary has previously suggested he could resign if a differential arrangement was reached, but insisted Northern Ireland would not be given a competitive advantage over Scotland by the "carefully tailored" deal.

He said: "I have looked at the detail of the proposals for Northern Ireland and I have been quite clear I am not totally comfortable with those arrangements.

"If you weigh up what's the greatest threat to the integrity of the UK, my judgement is that's having no deal, chaotic Brexit from the EU - I regard that as the most unsatisfactory outcome in terms of standing up for the integrity of the UK."

When asked why Mrs May refused to rule out the damaging no deal Brexit he claimed to want to avoid, Mr Mundell said the draft deal was the only solution.

READ MORE: Brexit: SNP brand Theresa May a 'liar' over Irish backstop 

"She's making the case for her deal because her deal is the best way to avoid that threat," he said.

"Even Mrs May's most passionate critic couldn't say she has not done that as vigorously and with as much effort as could possibly have been done because... She believes that voting for that deal is way to resolve these issues."