Bob Mackenzie is reportedly refusing to pay back £1.2m in bonuses after he was fired for assaulting another senior AA employee last year

The AA has said it is “astonished” that former executive chairman Bob Mackenzie is taking it to an employment tribunal, and it will “robustly defend any action.”

Mackenzie was fired for gross misconduct last July after he became involved in a physical altercation, described by the AA as a “sustained and violent assault” on another AA employee, the head of its insurance arm, Michael Lloyd.

According to Sky News, the struggle came about because of tensions between Mackenzie and Lloyd over a possible merger with Hastings.

The broadcaster reports that Mackenzie is resisting the AA’s request that he repay £1.2m in bonuses, and it suggests that there may be more trouble to come for Mackenzie and the AA over a lucrative reward scheme that the ex-chairman was part of.

The full statement released by the AA reads: “We are astonished that Mr Mackenzie is taking this to an employment tribunal. We stand by our decision to dismiss him for gross misconduct following his unprovoked, sustained and violent assault on another employee of the AA, and will robustly defend any action.”