Richard Masters has insisted that amendments made to sponsorship rules were 'lawful' after Manchester City launched a fresh legal challenge against the Premier League.

These regulations, which were first introduced in the aftermath of Newcastle United's takeover, ensure all commercial deals with companies linked to a club's owner are independently assessed to establish they are of fair market value. Newcastle joined Manchester City, Aston Villa and Nottingham Forest in standing against proposed changes to the rules back in November, after the champions' previous legal challenge found some aspects of the regulations to be 'unlawful', but the other 16 clubs voted them in.

However, it felt inevitable that Manchester City would act once again after Simon Cliff, the club's legal counsel, warned of further proceedings if the amendments were 'rushed through'. Masters, the Premier League's chief executive, has since informed clubs that Manchester City have 'begun a further arbitration to challenge the APT rules'.

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"Manchester City FC seeks a declaration that the amendments approved by clubs in November (and therefore the current APT rules in force) are unlawful and void," an excerpt of Masters' letter read. "The Premier League remains strongly of the view that the amendments passed in November were lawful and the APT rules comply with all competition law requirements.

"We consider that the new arbitration must be resolved as soon as possible and, to that end, have agreed that the same tribunal should be appointed to hear the new case. The parties are currently corresponding in relation to further directions.

“The APT rules remain in full force and effect and clubs remain required to comply with all aspects of the system.”