A formal complaint against the BBC has been launched by two top SNP figures accusing the corporation of deliberately demoting the status of the third party at Westminster.

SNP depute leader and Westminster leader Ian Blackford raised "two formal complaints" against the broadcaster in a joint letter, according to an exclusive report in The National.

The senior figures in the party accused the BBC of downplaying the role the SNP has at Westminster because they represent Scotland. They also say that the broadcaster under-represents them on flagship BBC shows.

It comes after the BBC cut away from the SNP's Ian Blackford twice as he was speaking after statements from Theresa May and Jeremy Corbyn on the main BBC channels. They also cut away from the Commons just as Blackford was standing up to give his opening remarks in the original debate over May’s deal on Tuesday.

BBC One, which showed both Theresa May’s statements and Jeremy Corbyn’s responses, would likely have had an average audience share of around 22.25%. Ian Blackford’s speech was broadcast on the BBC Parliament channel, which has an audience share of just 0.06%.

In a letter to the BBC the senior SNP figures wrote: "So far this week we have seen three consistent and deliberate editorial decisions taken to cut off parliamentary coverage on News Specials from the moment Ian Blackford spoke in the House of Commons. The consequence of these editorial decisions is to relegate the third party at Westminster"

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The pair also say the BBC is “in breach of its mission and responsibility” to serve licence fee payers across every UK country, erasing the SNP from its coverage by “consistent and deliberate editorial decisions”.

The letter continues: “This pattern of behaviour follows recent research and media reports which revealed that Newsnight did not feature a single SNP politician in the entirety of February.

“And in January, the revelation that Politics Live had just two SNP guest slots out of a total of 79 guest slots.

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“We would like to understand how the BBC believe they are serving the audience in Scotland in each of these examples.

“Therefore, regarding our first complaint, it is our contention that BBC coverage of Westminster parliamentary business is suggestive of a deliberate policy of BBC editors and managers to demote the status of the third party at Westminster because that party represents only Scotland.

“Regarding our second complaint, we contend that the under-representation of the SNP from flagship programmes such as Politics Live and Newsnight provide evidence of a continuing failure by the BBC – set out over a decade ago in the highly critical King Report – to serve all audiences in the UK in equal measures."

A BBC spokesperson confirmed to us: “We have received the letter and will respond directly in due course.”

You can read the full story in The National