Jamie Oliver’s restaurant empire is calling in administrators, putting more than 1,000 jobs at risk, The Guardian reports.

The company, which includes 23 Jamie’s Italian outlets, plus the Fifteen and Barbecoa restaurants, is understood to be appointing KPMG as administrator.

Oliver said: “I am deeply saddened by this outcome and would like to thank all of the staff and our suppliers who have put their hearts and souls into this business for over a decade. I appreciate how difficult this is for everyone affected.

“I would also like to thank all the customers who have enjoyed and supported us over the last decade, it’s been a real pleasure serving you.

“We launched Jamie’s Italian in 2008 with the intention of positively disrupting mid-market dining in the UK high street, with great value and much higher quality ingredients, best in class animal welfare standards and an amazing team who shared my passion for great food and service. And we did exactly that.”

The group had been seeking buyers in recent months after Oliver decided to sell up amid heavy competition in the casual dining market that has already seen chains such as Carluccio’s, Byron Burger and Gourmet Burger Kitchen close outlets.

The administration comes after sales at Jamie’s Italian dived by nearly 11% last year to £101m as it closed 12 restaurants and made about 600 staff redundant.

The chain was only saved from bankruptcy by a last-minute £13m injection of cash from Oliver, part of almost £17m of new funding provided to keep the restaurants afloat.

Oliver got his big break when a visiting TV crew spotted him while he was working at the River Cafe in Hammersmith in 1997, leading to his own show The Naked Chef.

Since then he has built a TV, publishing and restaurant empire which has had its ups and downs.