Mhairi Black has said she will be standing down at the next General Election.
The SNP’s deputy Westminster leader said she will not seek re-election.
Black, who was the youngest MP ever elected to the House of Commons when she won her seat in 2015 said she is “tired”.
In an interview with Emily Maitlis on the News Agents Podcast she revealed her decision.
She hit out at the culture of Westminster, branding it ”toxic and poisonous”.
Black said: “I’m tired, is a big part of it. The thing that makes me tired is, Westminster is one of the most unhealthy workplaces that you could ever be in.
“It’s a toxic environment. The entire design of the place and how it functions is just the opposite of everything I find comfortable.”
Asked if she meant it was poisonous, she agreed.
She said: “It’s definitely a poisonous place.”
The Paisley and Renfrewshire South MP said she has spent too much of her life in Westminster.
She said: “In the runup to the next election it will be nearly ten years I’ll have been there.
“A third of my life I’ve spent in Westminster, which gives me the ick.
“I don’t regret doing any of what I’ve done. I’ve been fighting for what I believe in.”
Her youth, compared to many other MPs, she said gives her a different perspective.
She added: “I can understand why people get absorbed into the world of Westminster and can spend 30, 40 years there.
"It's got its own culture its own history, which is still alien to me.”
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