The future of almost 300 jobs are in doubt after parts of a Wearside leisure group called in administrators.
Principle North East, Principle Yorkshire and Principle Midland are trading subsidiaries of the Washington-based Principle Leisure Group.
They operate about a dozen bars in the north-east of England, Nottingham and Sheffield, but have run into cash-flow problems and amassed tax debts.
All venues will be operate under licence until a buyer can be found.
Joint Administrator Andrew Haslam, from Begbies Traynor, said: "The group operates the Popolo branded bars in Newcastle, Sheffield and Nottingham, along with a number of additional outlets.
"It encountered cash flow difficulties due to the opening and refurbishment of several new outlets and the general downturn in the licensed sector, resulting in tax arrears being accrued.
"The outlets are now being operated under licence whilst a purchaser is sought.
"The process undertaken will, at least in the short-term, protect the contracts of over 300 employees and offer the group the best opportunity to identify a purchaser."