Showbiz
Rex Features
Sir Paul McCartney's ex-wife has now been ordered to submit plans for the feature, which will have to be demolished if permission is refused.
Planners discovered the pool while visiting the East Sussex property to ensure an illegally erected marquee had been removed.
A spokesperson for Rother District Council told The Hastings & St. Leonards Observer: "The marquee appears to have been dismantled.
"Apparently there is a swimming pool and we have invited a planning application for it. This will then be considered in accordance with the normal planning process."
Mills purchased the property in 2007 following her split from McCartney.
More: Heather Mills, Showbiz
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