Stewart Hosie has said sorry for the sex scandal that rocked the SNP and announced he will quit as the party’s deputy leader.
The Dundee East MP, 53, will not stand for reelection at the Nationalists’ autumn conference following reports both he and fellow SNP MP Angus MacNeil, 45, had separate affairs with 36-year-old Westminster journalist and former actress Serena Cowdy.
His separation from his wife of 20 years Shona Robison, the Health Secretary, was announced last weekend.
In a letter to the First Minister, Mr Hosie said: “I am writing to you firstly to apologise for any hurt and upset I have caused to friends, family and colleagues. That was never my intention.”
Mr Hosie added “the stress of the intense scrutiny of my private life” in the wake of the lurid revelations had damaged his health.
Mr Hosie, who has suffered from serious health conditions in the past, will continue in his role until the SNP’s annual conference, to be held in the autumn.
Ms Sturgeon paid tribute to Mr Hosie’s work as depute leader but did not mention his health in her response.
The SNP leader is extremely close to Ms Robison having once described her as “one of my closest friends and colleagues”.
She was photographed embracing the Dundee City East MSP in the Holyrood chamber last week and failed to back Mr Hosie to continue in his role afterwards.
Ms Sturgeon, who will address her MPs at Westminster on Monday, also paid tribute to Mr Hosie’s work on the 2015 and 2016 SNP election manifestos.
She wrote: “Your decision to make this known now will allow an election for your successor to be conducted in advance of the Autumn conference.”
Nicola Sturgeon and Stewart Hosie after they were confirmed as leader and deputy in 2015.
Early speculation tipped Humza Yousaf, the new Transport Minister, to be the front runner to replace Mr Hosie.
Other contenders could include previous candidates Angela Constance and Keith Brown, as well as highly regarded MPs such as Mhairi Black and Hannah Bardell.
Scottish Conservative MSP Jackson Carlaw has reported both Mr Hosie Mr MacNeil, to the Parliamentary Standards Commissioner over allegations they claimed expenses for accommodation while carrying out extra-marital affairs with Ms Cowdy.
Ms Sturgeon said she had seen no evidence of any breach of rules.
Labour’s Shadow Scottish Secretary, Ian Murray, said: “This incident hasn’t just seen them let down their party, but they are letting down the people of Scotland who voted for them and expect much better behaviour.”