Mike Ashley takes legal action against Newcastle co-owner Amanda Staveley

• Ashley claims Staveley has breached terms of a loan

• Matter relates to club’s removal of Sports Direct signage

Mike Ashley has initiated legal action against Amanda Staveley, the co-owner of Newcastle United, for allegedly breaching the terms of a £10m loan he provided in order to help facilitate the club’s £300m sale to a Saudi Arabian led consortium last October.

A representative of Staveley, who has a 10% stake in Newcastle while Saudi Arabia’s Public Investment Fund (PIF)has an 80% controlling interest and the property developers Reuben Brothers another 10%, said on Friday night she was “very confident” of successfully defending Ashley’s attempt to secure the immediate return of the loan.

Ashley, who owned Newcastle for 14 years, alleges that, by removing the signage promoting his company Sports Direct from St James’ Park Staveley has reneged on an agreement to continue advertising his business at the stadium until the end of this season.

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Documents submitted at the high court in London by the retail magnate’s legal team reveal he wants the loan repaid immediately and also claim the Yorkshire-born financier has broken another pledge not to criticise his stewardship of the club in the media.

Ashley is jointly suing Mehrdad Ghodoussi, Staveley’s husband, for his role as guarantor of the supposedly two-year loan intended to cover, among other things, Staveley’s legal costs incurred during the purchase of Newcastle.

Documents relating to the case deposited by the retailer’s lawyers also suggest that Staveley funded her 10% share in Newcastle thanks to a £30m loan from Reuben Brothers.

A spokesperson for Staveley and Ghodoussi said the couple, who have a management contract to run Newcastle on a daily basis, “do not intend commenting on the litigation but are very confident of successfully defending the claim in full”.