Mike Ashley has launched an attempted boardroom coup at online fast fashion retailer Boohoo, pitting the retail tycoon against rival entrepreneur Mahmud Kamani for control of the company’s future.

The Sports Direct founder has demanded a shareholder vote to appoint him as Boohoo’s new chief executive after Mr Ashley’s Frasers Group amassed a 27pc stake in the business.

In a scathing letter, Frasers claimed “incompetence” had sparked a “leadership crisis” at Boohoo, adding that the board had “lost its ability to manage Boohoo’s business and investments”.

The letter accused Mr Kamani, Boohoo’s executive chairman, of refusing meetings with Frasers executives in their attempts to secure a board seat.

Mr Ashley’s representatives held a meeting with a non-executive director on Oct 18, where Frasers issued a 48-hour ultimatum to appoint Mr Ashley as the company’s chief executive. It comes as John Lyttle, Boohoo’s current boss, prepares to step down after five years. Frasers said it had yet to receive a response.

“We recognise stone-walling when we see it, and these tactics of ‘delay and ignore’ are no longer tolerable in the context of the continued value destruction that the Board is overseeing at Boohoo,” Frasers said in its letter.

Boohoo said its board was “in the process of reviewing the content and validity of the requisitions with its advisers” and promised a “further announcement” in due course. A search is under way for a new chief executive and Mr Lyttle currently remains in post.

Shares in Boohoo have fallen by 24pc so far this year, while its revenues have dropped by more than a third over three years. Its shares were changing hands at 28p on Thursday, up nearly 5pc on Mr Ashley’s intervention.

Both self-made fashion moguls, Mr Ashley and Mr Kamani have clashed over past deals, going head-to-head bidding for failed department store Debenhams, with Mr Kamani securing the takeover. Frasers was left ￡150m out of pocket after building up a 30pc stake in the department store chain before its collapse in 2020.

Mr Kamani launched Boohoo, which also owns PrettyLittleThing.com , in 2006. Mr Kamani’s father moved to Manchester from India via Kenya and initially made money selling handbags on a market stall, before founding the family’s textiles business supplying the likes of Primark and Marks & Spencer.

Boohoo, which markets budget dresses aimed at social media-savvy gen Z and millennials, went public in 2014, but since the pandemic it has lost close to 90pc of its value. It has struggled to compete with Shein, a fast fashion rival that ships products directly from China to cut overheads.