Angus MacNeil has been suspended from the SNP’s Westminster group after he clashed with the party’s chief whip on Monday.
The Western Isles MP later accused Brendan O’Hara of bullying, following the “tense exchange” in the House of Commons.
STV News understands this was about his attendance in parliament.
He is said to have shouted that O’Hara was a “small wee man” before throwing letters on the floor.
Stephen Flynn has now suspended the whip from MacNeil for one week.
MacNeil told STV News: “Stephen has his views and I have mine but as leader he has his own pressures to balance and I accept the decision he has taken.”
Following the clash with O’Hara, MacNeil tweeted: “General advice — Always stand up to bullies, — esp any abusing their positions — particularly those who scurry around shouting to anyone listening, ‘I’ll get him, I’ll get him, I will get him! — mark my words’.
“These are people, who from school, we should get taught to face down.”
The SNP figure also shared a reply to his tweet, which said: “Yes. They are cowards. They can never operate without a similar wee clique of nasty cowards around them.
“They’re also never intelligent people, or they wouldn’t behave that way to cover it.”
MacNeil, who was in the Commons since 2005, has been a vocal critic of the SNP and criticised its independence strategy and its policy on protected marine areas.
He also previously called for Nicola Sturgeon to be suspended from the party.
Scottish Conservative chairman Craig Hoy said: “The scandal-ridden SNP are clearly in a state of open warfare, with personal feuds spilling into public.
“Perhaps this is the ‘toxic’ culture Mhairi Black was lamenting when she became the sixth SNP MP to announce they were stepping down at the next election.
“It’s telling that Angus MacNeil has been suspended by the leadership for a fallout with the chief whip, yet Nicola Sturgeon retains the whip – contrary to party precedent – despite having been arrested.
“But this ugly soap opera doesn’t just affect the SNP – it impacts all of us.”
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