Scottish Tory leader Douglas Ross was forced to apologise during First Minister's Questions after a microphone caught him swearing at protesters disrupting parliament. 

In what has become an almost weekly occurrence, Climate Change activists in Holyrood's public gallery interrupted the weekly session, urging MSPs to "pause all new oil and gas".

On Thursday, the disturbance came as Mr Ross pushed Nicola Sturgeon on the Scottish Government's under-fire Deposit Return Scheme.

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As Presiding Office Alison Johnston suspended parliament, the Tory leader could be heard saying "f***'s sake." 

Initially, when parliament resumed, Mr Ross said: "I have to say it's getting very tiresome, these constant interruptions in First Minister's Questions.

"We are here, democratically elected to put questions to the First Minister and when it gets disrupted like that people watching and people who want to hear the questions and the answers are getting pretty fed up by that childish behaviour."

He said he had been "kinda on a roll, explaining the total political opportunism of the SNP."

Responding, Ms Sturgeon said: “Douglas Ross said that he was on a roll - I’m not sure whether he means rolling down the hill?”

At the next question, after it was pointed out that his outburst had been overheard, Mr Ross said: "Presiding Officer, can I begin with an apology, It's been brought to my attention that I perhaps used industrial language in response to the protesters who interrupted the session earlier.

"And to you and the chamber and everyone listening, including my mother, probably, I apologise for that."

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SNP MP Christine Grahame then asked the Tory leader what he had said, but Mr Ross declined to repeat his remark. 

Yesterday, the SNP's Westminster leader Stephen Flynn went viral after he was caught on camera saying "what the f*** was that" after Sir Keir Starmer made a bizarre reference to early 80s TV show Auf Wiedersehen, Pet during Prime Minister's Questions.