The Competition and Markets Authority’s (CMA) has extended its deadline for a final decision on the proposed merger of Sainsbury’s and Asda by eight weeks.

The regulator said that the “scope and complexity of the investigation” meant that the original deadline of March 5 had been pushed back to April 30 to “reach a fully reasoned provisional decision.”

The CMA said in a statement: “In taking this decision, the Inquiry Group had regard to the scope and complexity of the investigation and the need to consider issues raised by the main parties’ and third parties’ submissions, and the need to reach a fully reasoned provisional decision.

“Moreover, it is necessary to allow sufficient time to take full and proper account of comments that will be received in response to the Inquiry Group’s provisional findings and to reach a fully reasoned final decision in the statutory timeframe.

“In light of the above, the Inquiry Group considers that there are special reasons why the report cannot be prepared and published within the reference period.”

The CMA launched an in-depth, phase two investigation into the proposed merger in September last year, led by an inquiry group chosen from its independent panel members, after the planned merger was announced in April 2018.

The regulator’s main priority was assessing whether shoppers would face higher prices or lower quality of service as a result of the merger and, if so, to prevent that from happening.