The UK's competition watchdog has launched an investigation into William Grant & Sons' prospective purchase of The Famous Grouse from Edrington.

The Macallan brand owner announced it had agreed to sell the Scotch whisky brand in September. The deal also includes Naked Malt whisky.

In a statement today, the Competition Markets Authority (CMA) said it had initiated the probe to assess whether the deal would create "a relevant merger situation under the merger provisions of the Enterprise Act 2002" and if it consequently could decrease competition both in the UK and "any market".

The CMA has asked for comments on the deal "from any interested party" by 12 February.

An outcome on the first phase of the investigation is expected by 27 March.

Commenting on the transaction when it was announced in September, Edrington said the disposals – via its the 1887 Company subsidiary – were “the next stage of the company’s mission to be the world’s best at crafting exceptional ultra-premium spirit brands”.

The remainder of the company's portfolio includes Brugal rum, The Glenrothes single malt Scotch, and No. 3 London Dry Gin.

Edrington CEO Scott McCroskie said at the time the move marked the company's departure from blended Scotch and was “driven by our strategy to focus on our core strengths and the growth opportunities in the ultra-premium spirits category".

William Grant is known for its Scotch whiskies such as Glenfiddich, Grant’s and The Balvenie. It also produces gin, rum, Irish whiskey and liqueurs through Hendrick’s, Sailor Jerry, Tullamore Dew and Drambuie.

A spokesperson for William Grant in September said the purchase of The Famous Grouse "would be a significant addition to our portfolio", adding it had "potential for innovation and international growth in a number of markets".