The merger will create a company with over 170,000 employees and annual revenues of nearly £30 billion.

The group will operate nearly 600 supermarkets, 700 petrol forecourts and 100 convenience stores, serving over 20 million customers each week.

The deal is expected to be announced on Friday and will be structured as an acquisition of EG UK by Asda, costing around £1.25 billion.

The combination of the two companies will create one of Britain's biggest private sector employers and is expected to generate significant synergies.

The Competition and Markets Authority has already closely scrutinised the implications of Asda and EG being controlled by the same shareholders when the supermarket chain was acquired by them for £6.8 billion.