CEO Stuart Machin anticipates that M&S's online operations will be fully restored within the next four weeks, with the majority of the attack's impact resolved by August.
While online sales for certain fashion and home ranges have partially resumed, services like click and collect and next-day delivery are still being reinstated.
Chairman Archie Norman stated that executive pay deals, including CEO Machin's recent 39 per cent increase to £7.1 million, could be impacted by any financial performance drop caused by the cyber attack.