MYSTERY surrounds a cryptic tweet from Michelle Mone as the Ultimo underwear firm she set up 21 years ago announced it is to cease trading in the UK.

The Tory peer, now known as Baroness Mone of Mayfair, established the lingerie brand – whose models have included Penny Lancaster and Rachel Hunter – in 1996.

The firm achieved international success after actress Julia Roberts reportedly wore an Ultimo bra in the hit 2000 film Erin Brockovich.

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Breaking her silence in a now-deleted tweet, Lady Mone, 46, said: “It’s sad to see the Ultimo brand that I created 21 years ago and turned it into a global business is closing down. 17 worldwide inventions, 1 billion in press, some of the biggest stars in the world.”

Signing off on a more mysterious note, she added: “Please NOTE that I sold Ultimo 4 years ago and left that day. I know exactly what went wrong.”

Glasgow Times:

Minutes after removing the message from her account, the Glaswegian posted another, slightly amended reaction, which read: “It’s very sad to see that Ultimo,the brand I created 21 years ago is closing down. I turned Ultimo into a global success story and I am immensely proud of what we achieved.”

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The end of this one, however, said: “Please note that I sold Ultimo and left the company 4 years ago. I may comment further shortly, when the time is right.”

Sri-Lankan based MAS holdings acquired a majority shareholding in parent company Ultimo Brands International in 2014, with Lady Mone resigning as a director the following year.

Glasgow Times:

Now the firm has announced that following an extensive review of the business, the operation in the UK will cease trading.

Staff at the Ultimo headquarters in East Kilbride were informed, with a formal redundancy consultation under way with the 11 employees there.

Retail partners and suppliers have also been told of the decision.

An Ultimo spokesman said: “The last few years have been extremely challenging for Ultimo, driven by increasing competition in the market and more cautious consumer spending due to the uncertainty surrounding the UK economy over the last 18 months.

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“Having reviewed the business’s performance over the last three years as well as future prospects and considering the retail environment within which the business is operating, the board has, with regret, decided to cease operations of the Ultimo business in the UK.”

The spokesman added the company “would like to thank all staff, customers and suppliers for their commitment, support and loyalty to the Ultimo brand over the years”.

Ultimo’s UK operations will be wound up at the end of June, with the company pledging to honour financial commitments with suppliers and partners.

Its website will continue trading until April 15, with Ultimo products still available while stocks last.