It is understood the top City lawyer, who took a year's sabbatical to spearhead owner Mike Ashley's vision for the future at St James' Park, could leave the club within a matter of weeks.

Mort has overseen the transition from the Shepherd era and a restructuring of the club during his chairmanship, and his reign has been far from uneventful.

He initially arrived on Tyneside to work alongside Shepherd, who had earlier sold his shares to Ashley to ease him towards a £134.4million takeover, but was quickly handed the reins as the former chairman ended his long association with the Magpies.

Sam Allardyce was already in place as manager when the pair arrived, but having overseen his summer recruitment drive, backed by a relatively modest net investment of around £10million, they dispensed with his services in January after a dreadful run of results.

They sprang a major surprise when they replaced Allardyce with Kevin Keegan, and although even he found the going tough in the early stages, the club's Premier League status was secured long before the campaign drew to a close.

However, it is away from the football side of things that Mort has done much of his work, overseeing a drive to address Newcastle's £100million debt burden and working to improve the club's image both inside and outside the city.

The Magpies are yet to confirm Mort's departure, or the identity of his replacement.

But significantly, Ashley's long-term associate Derek Llambias was appointed deputy chairman earlier this month and it would be no surprise if his name was high on the list of potential successors.