South African retailer Foschini Group, which bought Phase Eight last year, is thought to be considering a bid for Whistles.
Whistles has called in advisers at KPMG to prepare for a sale and is already fielding interest from a clutch of prospective buyers, the Sunday Telegraph reports.
If Foschini succeeds, it will be the latest South African company to snap up a British retailer, following a wave of deals.
Last year Brait, the investment vehicle controlled by South Africa’s richest man, Christo Wiese, bought New Look in a £1.9bn deal, while Truworths acquired footwear business Office for £256m.
It is not clear whether prospective buyers are being offered a stake or full control of Whistles.