Former SNP minister Fergus Ewing is at risk of losing the party leadership after voting to sack Green Party minister Lorna Slater.
Bosses are considering suspending the Inverness MSP from the Holyrood group as part of disciplinary action.
Mr Ewing – who is not in Parliament this week – said he had not heard from SNP leaders or people since his decision to vote against Ms Slater.
However, party sources said they are now discussing how to discipline Mr Ewing, which could mean losing the whip and being forced to sit as an independent.
The decision comes despite the former Minister for Rural Economy facing no action when complaints of bullying were made against him.
SNP sources say Mr Ewing – who has become increasingly critical of Humza Yousaf’s government – has “crossed the line” by backing a Tory motion against Ms Slater.
The Green Party minister survived a no-confidence vote in Holyrood after the SNP and the Scottish Greens backed her – with the Conservatives, Labor and Liberal Democrats calling for her to examine the collapsed deposit-return scheme.
Mr Ewing sided with opposition MPs when he claimed Ms Slater “does not enjoy the confidence of business”.
He said: “I have therefore voted to appoint a new minister to take on this difficult matter, to deal with the huge fallout from numerous claims for damages and to reconsider how recycling targets can best be met.”
But hours after the vote, it emerged that Mr Ewing was now at risk of expulsion from the SNP – the party whose mother Winnie Ewing was previously both president and politician.
She rose to prominence after winning the Hamilton by-election in 1967, saying, “Stop the world, Scotland wants to move on.”
SNP sources said Whips are considering what action to take against Mr Ewing.
During his reign he was already the subject of a complaint of bullying. Nicola Sturgeon has repeatedly refused to release the outcome of an investigation into the allegations, fearing it would “deter” future complainants.
Mr Ewing was sacked from government in 2021 as the former First Minister reshuffled her top team.
He has since openly criticized the work of his former colleagues – and in May this year he furiously tore up a new fisheries protection plan and warned the Scottish Government’s plans were an “executive notice” for the industry.
Should Mr Ewing lose the whip, it will add further pressure to Mr Yousaf for failing to expose Ms Sturgeon to the whip following her arrest.
She has refused to resign and her ex-mentee refuses to force her to do so, despite demands from some members of the SNP.
Revelations about the potential suspension came as business leaders praised Mr Ewing for his “great courage and integrity” in speaking out against the DRS.
This comes after the program in Scotland was postponed until October 2025 at the earliest and companies have warned of the impact it will have on them.
Ms Slater’s decision to delay the program further drew criticism from some, as Circulatory Scotland – which was set up to run the DRS – was forced to appoint administrators.
Business leaders said it was a “completely backward situation” that Mr Ewing could threaten to lose the SNP party leadership while Ms Slater remains in office.
The letter is signed by dozens of Scottish drinks industry figures including Edinburgh’s Stewart Brewing, Avva Scottish Gin from Elgin, Shipyard Gin in Gourock, Wild Thyme Spirits on the Isle of Colonsay and the North Uist Distillery and Bon Accord soft drinks companies in Edinburgh.
In the letter, the business leaders said they were grateful to the MSP for his “efforts to persuade your colleagues to stop the program.”
They added: “Thank you again for your leadership and commitment to advocating for the interests of business in Scotland.”
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