In a letter to HMRC, Walker said he is “totally shocked and amazed” that the government department is chasing Iceland for more information on the scheme “under the current conditions”.

As previously reported, Iceland has been accused by HMRC of breaking minimum wage rules around the savings scheme for its staff.

Employees can choose to have money deducted from their pay packets, which is saved in a dedicated account and typically withdrawn at Christmas.

HMRC has argued that, as a result, their pay had technically not met the minimum wage regulations.