A string of harassment allegations said many complaints were deliberately ignored. (File)

People working for lawmakers in Britain's lower house of parliament face an unacceptable risk of sexual harassment and bullying, which has been hidden because staff fear reprisals, according to a official report released on Thursday.

Staff in the House of Commons are subject to "sometimes forceful" unwanted sexual advances and sexist comments are regularly made about women who work in politics, it said.

The report commissioned after a string of harassment allegations said many complaints were deliberately ignored.

Sexual harassment is "a problem, with staff being subject to unwanted sexual advances, often accompanied by touching, sometimes forceful," the report said.

"A minority of Members of Parliament have bullied and/or harassed staff in the past and continue to do so, despite the introduction of the new Parliamentary Behaviour Code."