Mainstream bills itself as an organisation made up of people from different political backgrounds who wish to “banish extremism from British politics once and for all”.
It calls for political disagreements to be conducted within the realms of responsible debate and said it will promote respectable politics and oppose extremism on all sides of the political spectrum.
Its members include Conservative peer Lord Eric Pickles, former Labour MP Mike Gapes and television presenter Rachel Riley.
Kirsty Buchanan, a former political editor at the Sunday Express, was most recently at the Ministry of Housing, Communities and Local Government (MHCLG), where she was director of comms.
Buchanan was suspended from her job at the government department in January after less than a year in post amid allegations of bullying, following an investigation during the December general election.
The department later confirmed that she had left the role, which commands a salary in excess of £90,000. It is not known who complained about Buchanan and MHCLG declined to elaborate on the specific nature of the claims.
Educated at Watford Grammar School for Girls, Buchanan went to Kingston University.
After graduating in 1991, she embarked on a career in regional and national newspapers and rose to become political editor at the Sunday Express in 2009.
She left journalism in 2014 and took a job as deputy comms director at the Department for Communities and Local Government.
Little more than a year later, Buchanan left to become head of comms at West Sussex County Council.
During her time there she was embroiled in a dispute with the Argus newspaper over the media handling of the memorial service for victims of the Shoreham Airshow crash, with local newspapers banned from attending.
Buchanan failed in an attempt to get IPSO to censure the newspaper over its coverage of the controversy.
She went on to work as a special adviser to Liz Truss during the Conservative MP’s brief stint as justice secretary, before moving to 10 Downing Street in August 2017 as head of political press.
Mainstream had not responded to a request for comment on Buchanan's appointment at the time of publication.
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