The SNP has threatened legal action against Sky News after accusing the channel of failing to meet their “statutory obligations as a broadcaster” over the decision to freeze the party out of their pre-election debates.

Sky unveiled plans for a hustings programme with Boris Johnson, Jeremy Corbyn and Jo Swinson on November 28. The news channel only promised to “continue to provide appropriate coverage to other parties in broadcasts throughout the election period.”

In a letter to Sky’s head of news, reported first in our sister paper The National, John Ryley, the SNP’s business convener Kirsten Oswald said the omission of her party “fundamentally fails the electorate at what is a crucial time for the UK and critically, we believe, fails to meet your statutory obligations as a broadcaster.”

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The former MP told Ryley it is “inexplicable that instead of inviting the SNP, the third largest party in the UK Parliament at the two most recent elections, you have instead invited one of Parliament’s smaller parties which at the last election secured only a third as many seats as the SNP”.

She described the proposal as “a democratic outrage that short-changes the whole of the UK”.

Oswald cited sections 5 and 6 of the Ofcom code which states that Sky are bound to ensure that “an appropriately wide range of significant views must be included and given due weight in each programme”.

She added: “If this fundamental issue of democracy is not resolved to our satisfaction, we reserve the right to test the matter in the courts.”

HeraldScotland:

The First Minister herself was asked about the row during an interview on Sky yesterday morning. Nicola Sturgeon told Kay Burley that the decision was undemocratic.

Asked by Burley if she was “cross”, the First Minister replied: “I don’t want to personalise it, but I think all broadcasters really need to consider whether they’re reflecting politics as it is or as they’d like it to be.”

Nicola Sturgeon added: “If I may say for Sky in particular who, to its great credit has been arguing for these decisions to be taken away from politicians, and arguing for an independent debates commission, something the SNP has supported, to take a decision on a debate that defies democracy.

READ MORE: Decision to omit SNP from Sky election debate 'defies democracy' says Nicola Sturgeon

“I think is particularly regrettable and I think the broadcasters have to take a long hard look at themselves, but to other party leaders, particularly to Corbyn and Johnson, what are you scared of in terms of having a real debate?

“Why are you so scared to have the SNP’s voice heard?

“To the broadcasters, reflect democracy as it is, do your jobs properly.

“And to the other party leaders, stop running scared.”

Scottish LibDem leader Willie Rennie said it was up to the First Minister to make her own case for appearing on the debates. He said: “There’s no doubt the Libs Dems have had a big increase in support right across the United Kingdom.

“We are a party that’s standing right across the country so we’ve got a UK-wide platform.

“It’s up to Nicola to make her own case for that and I’m sure she’ll make that quite forcefully.

“But we’re doing our part in trying to make sure it’s not just the old boys’ network – two leave parties arguing against each other in the debate.”

Meanwhile, a Plaid Cymru spokesman said the Sky debate, proposed for Thursday November 28, is one “harping back to a politics that no longer exists”, adding: “Every vote in Parliament is likely to count.

"Shutting out the third biggest party – the SNP – is lunacy, but in the last three years, Plaid Cymru’s votes have been an equally crucial factor on key issues in Parliament.

ITV will host a head-to-head debate with Johnson and Corbyn.