SNP MP Stewart McDonald has branded Dennis Skinner a “thug” after the veteran Labour backbencher accused the Scot of being a “piece of shit” and then defended the comment by saying he was just putting him in his place.

The Glasgow South MP took to Twitter to vent his frustration with the so-called Beast of Bolsover who often shares a bench in the Commons with the SNP.

He said Skinner was so loyal to Jeremy Corbyn that  criticism of the Labour leader from SNP MPs prompted a furious reaction.

McDonald tweeted: “A new parliamentary habit seems to be forming, whereby any time an SNP MP sat behind Dennis Skinner verbalises any frustration about what Jeremy Corbyn says, he angrily turns round to tell us off.

“He has just turned round and called me a ‘piece of shit’.

“He has become a thug.”

Labour backbenchers heckled McDonald when he then used a point of order on the floor of the Commons to raise Skinner’s conduct with speaker John Bercow.

The two had already spoken privately about the issue with Bercow telling McDonald to raise it informally with Skinner.

But the SNP MP said he felt he had little option but to raise this formally after Skinner showed “no sign of having any regret about it”.

He said the Bolsover MP had defended the comment, telling a journalist that “he was just putting me in my place".

Bercow replied to say “moderation and good humour” with the “best definig feature of Parliamentary combat. We should be able to disagree with each other agreeably”.

He then said he had known skinner for 21 years, and held him in the highest esteem and that he was not going to “criticise a member for conduct that I didn’t witness".

Later McDonald tweeted: “Having raised this as a point of order with the Speaker, the most telling response wasn’t that Mr Skinner sat there in silence but was the braying from Labour MPs trying to shout me down. It used to be the case that Labour were against abuse in the workplace. Apparently not now.”

The 86-year-old Skinner has been an MP since 1970, and is known for his forthright views.

He was one of 36 Labour MPs to nominate Corbyn as a candidate in the Labour leadership election of 2015.

He has been suspended from Parliament on at least 10 occasions, usually for "unparliamentary language" when attacking opponents.

In 1984 he called David Owen a "pompous sod" and in 1992 called Tory John Gummer as a "little squirt of a Minister" and a "slimy wart on Margaret Thatcher's nose".

He was suspended in 2016, for referring to David Cameron as "Dodgy Dave" because of questions over the then Prime Minister’s tax affairs.