Mrs Watts regularly entertains buyers at her 240ha Halsdon Arabians stud near Dolton, Devon, and every august breeder from Europe, the Middle East and the US converge on it to assess its foals.
The business, founded more than 20 years ago, is estimated to be worth around 10 million, although that is dwarfed by the 100 million or more earned by Watts' music career.
"I am going to sue them because of the way they treated my mares.
"They also kept me in the dark," Mrs Watts told the Guardian.
The Polish Government sacked the management board of Janow Podlaski and fired Marek Trela, its director.
His replacement by Marek Skomorowski attracted the ire of influential figures in the Arabian horse breeding world.