Labour has accused Reform’s Zia Yusuf of “straightforward racism” after he suggested the party’s frontrunner to replace Keir Starmer in the Holborn and St Pancras byelection was not British.

Sagal Abdi-Wali, a former child refugee from Somalia and the leader of Camden council, has been tipped as an early favourite to contest the London seat for Labour after the former prime minister’s resignation.

Yusuf, Reform UK’s home affairs spokesperson, posted on X last week: “The frontrunner being foisted on the people of Holborn by Labour to replace the former prime minister Keir Starmer in our parliament was born in Somalia. Do you understand what’s happening?”

The post, which has been viewed 8m times, drew sharp criticism from several senior Reform UK figures during the party’s conference in Birmingham at the weekend. Appearing on Sky News on Sunday, the business secretary, Jonathan Reynolds, also condemned Yusuf’s post as “straightforward racism”.

Asked by the presenter, Jon Sopel, for his thoughts on the message, Reynolds said: “Pretty straightforward racism, isn’t it? There’s a potential candidate referenced there; spent decades in this country, huge contribution to her local community, so I think that speaks for itself.”

When Sopel asked whether it was “plain racism”, Reynolds replied: “Absolutely.”

Yusuf has drawn significant criticism for his inflammatory comments on X in recent months, including from top Reform UK figures. Nadine Dorries, the former Conservative minister who defected to Reform UK last year, described the post about Abdi-Wali as “nasty”.

“It was a nasty tweet. Zia Yusuf is a brilliant man, and he’s a genius actually, and he’s an incredible communicator. I wish he closed down his Twitter account,” she told Times Radio.

Laila Cunningham, Reform’s candidate for mayor of London and the daughter of immigrants from Egypt, told the Standard: “I don’t know what he meant by that comment. I read it a few times.

“I didn’t understand what he meant by that comment. Of course, you know, that woman is British. She’s the leader of Camden council. I didn’t understand what he meant by that.”

Reform UK has been contacted for comment.

Abdi-Wali arrived in Camden as a child refugee from Somalia. She has worked for more than a decade as a volunteer and trustee for local charities and is a governor of two schools in the borough, according to Labour.

She was first elected as a councillor in 2022 and became the leader of the council in May, when she said: “Camden has been my home for 35 years. It is the place that gave my family sanctuary, that welcomed us, and that has shaped so much of who I am, what I stand for and what inspired my commitment to public service and to working for the community that welcomed us.”

Labour is expected to announce its candidate for the Holborn and St Pancras byelection by Wednesday. It faces a battle against the Green party to retain the seat as Zack Polanski, its leader in England and Wales, is expected to be confirmed as its candidate.