STEWART Hosie is to step down as the SNP's deputy leader, claiming his blood pressure has been affected by the recent "intense scrutiny" of his private life following allegations of a sex scandal.

The beleaguered MP has been under pressure after he was placed at the centre of an alleged love triangle involving fellow MP Angus McNeil and Westminster journalist Serena Cowdy.

Cowdy, who is now in a relationship with Hosie, previously had an affair with McNeil. 

Hosie and his wife, Scottish Government minister Shona Robison announced the end of their marriage just a day before news of the affair appeared in the Daily Mail.

In his letter to Sturgeon, Hosie apologised "for any hurt and upset I have caused to friends, family and colleagues. That was never my intention."

He goes on to tell the First Minister he will not seek re-election as Depute Leader of the SNP at this year’s annual conference, citing health reasons and a wish to spend more time on his constituents' needs.

"As you know I have been admitted to hospital on three occasions in the past few years with very high blood pressure. In that regard, the stress of the intense scrutiny of my private life has been very difficult.

"I intend to concentrate on my constituents, my responsibilities at Westminster, and most importantly, my health."

Responding, Sturgeon says she wishes Hosie well: “Thank you for your letter of earlier today advising me of your intention not to seek re-election as Depute Leader of the Party."

She continues: "I want to take this opportunity to thank you for your service as Depute Leader since November 2014. During your tenure in office, amongst your many other duties, you have authored two successful election manifestos - providing the policy platform for our victories in both the 2015 General Election and the 2016 Scottish Parliament election. These are achievements you should be very proud of."

It is understood Hosie will now no longer lead the SNP's summer push for independence. 

Nominations for the party's new deputy leader will close on August 5 with the result announced at the start of the autumn conference.

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