Santander Asset Management has dismissed claims it fired a female worker in the wake of her breast cancer treatment, saying it did so because she competed in a dressage competition during work hours and then lied about it.

Clair Gibson, who was global head of compliance at the €179bn fund manager between 2014 and 2017, told an employment tribunal in London on Tuesday that she was passed over for promotion and later fired because Santander felt her cancer treatment and recovery made her an "irritant".