In a statement, the company said it was considering the future of its Jamie’s Italian brand, which has over 30 restaurants in the UK.
It comes after Oliver shut six Jamie's Italian sites in the first quarter of 2017.
The group declined to comment on the number of restaurants which could potentially face closure this year, but said no decisions had been made ‘at this stage’.
“The Jamie Oliver Restaurant Group can confirm it is exploring plans to restructure its Jamie’s Italian restaurant estate in the UK, to ensure the business is in good shape for the future,” the company said.
“As part of this review, we are in conversation with our stakeholders, but no final decisions or proposals have been made at this stage.
“The review does not affect Jamie’s Italian international franchises managed through Jamie’s Italian International.
“The Jamie Oliver Media Group and the Jamie Oliver Licensing Group, which are both managed and run separately, are also unaffected.”
It follows a difficult year for Oliver's restaurant business. The group closed its sole remaining Union Jacks pizza site in Covent Garden last March, six years after the chef launched the concept.
Jamie’s Italian posted a £9.9m loss for the last financial year, with CEO Simon Blagden stepping down in October after heading up the business for nearly a decade.
BigHospitality’s sister site MCA reported in November that the group had brought in AlixPartners as an external advisor to work on its strategy for developing Jamie’s Italian and Barbecoa in the UK and overseas following Blagden’s departure.
Other groups including Strada and Polpo have already shut restaurants this year, while up to 20 Byron sites could be facing closure as part of a proposed restructure of the business.