BBC
Zia Yusuf has resigned as the chairman of Reform UK, saying "I no longer believe working to get a Reform government elected is a good use of my time".
In a post on social media, Yusuf did not expand further on his reasons for stepping down.
However, it comes after he called the party's newest MP "dumb" for calling on Sir Keir Starmer to ban the burka.
In a post on X, Yusuf wrote: "11 months ago I became chairman of Reform. I've worked full time as a volunteer to take the party from 14 to 30% [in national polls], quadrupled its membership and delivered historic electoral results.
"I no longer believe working to get a Reform government elected is a good use of my time, and hereby resign the office."
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