Former Blackburn manager Sam Allardyce has instructed lawyers to initiate proceedings against his Ewood Park successor Steve Kean, Press Association Sport understands.
The action comes in relation to unguarded comments made by Kean about Allardyce to supporters while secretly being filmed.
The four-minute video, apparently filmed during Rovers' pre-season trip to Hong Kong last summer, was released on the internet overnight.
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Cold, frosty with icy patches. Dry and sunny for many into Monday with winds lighter
Staying bitterly cold by day and night but as winds turn more northeasterly the Pennines provide shelter, meaning a mostly dry outlook....
Dry and sunny for many. Cold and clear with frost and ice overnight