The Labour MP Paulette Hamilton and singer Mel B are among leading Black Britons urging parliamentarians to make the UK the first western country to introduce a law to end afro hair discrimination.

The World Afro Day (WAD) campaign has written an open letter to MPs, calling on them to vote for the recognition and prevention of afro hair discrimination by updating the Equality Act 2010 to make afro hair a protected characteristic.

The letter has been signed by 100 campaigners and supporters, including the singer Beverley Knight, writer and campaigner Patrick Hutchinson, singer and presenter Fleur East, school leader Evelyn Forde MBE and Prof Patrick Vernon OBE.

It warns that the “omission of hair as a protected characteristic from the law has facilitated everyday discrimination and the normalisation of afro hair as inferior in every sphere of life”.

The letter is part of WAD’s 100 Voices, 100 Words campaign, for which each supporter has written 100 words on why the change in law is vital.

The campaign will host a drop-in clinic at parliament with Hamilton, the WAD founder Michelle De Leon, Hutchinson and the TV and radio presenter Sarah-Jane Crawford. They will be there with their children to “focus on the change for the next generation”.

Campaigners have long argued that British children are unfairly penalised in school for wearing natural styles and protective methods for the upkeep of their afro hair, while adults in UK offices also face discrimination, harassment and assault.

De Leon said: “Laws are actually there to tell people what is right and what is wrong and to protect minority groups from oppression, discrimination and injustice. We simply do not have the right laws in the UK to stop generations of Afro hair discrimination from continuing.”

Hamilton said: “As Birmingham’s first black MP, and as a mother to four daughters, I know the impact this campaign could have on my local community and on people with afro hair across the UK.”

Mel B, said: “The very first video shoot I did as a Spice Girl for Wannabe, the stylists took one look at my hair and told me it had to be straightened. My big hair didn’t fit the pop star mould. But I stood my ground – backed by my girls – and I sang and danced as me, with my big hair, my brown skin and I was totally proud of who I was.

“So yes, I’m proud to support World Afro Day in its call for the Equality Act to protect against afro hair discrimination in the UK.”