SNP MP Lisa Cameron has announced that she has defected to the Conservative party.
The East Kilbride, Strathaven and Lesmahagow representative was facing a selection contest to remain as the SNP’s candidate at the next general election.
She said she quit because of a “toxic and bullying” culture in the party’s Westminster group.
Scottish Tory leader Douglas Ross welcomed her to the party.
Dr Cameron claimed previously that she had been “ostracised” by the SNP after speaking out over the handling of allegations against former Westminster chief whip Patrick Grady.
She said it had led to the deterioration of her mental health.
Dr Cameron did not rule out standing down and triggering a by-election if she did not win the SNP nomination.
The MP, who was challenged by party staffer Grant Costello, had been due to find out the results of the selection contest on Thursday.
SNP sources have told the BBC she was expected to lose.
SNP Westminster leader Stephen Flynn said her claims of being ostracised “didn’t reflect” his experience of the situation in Westminster.
The SNP has been contacted for comment.
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