Debenhams says a local tribunal about an increase in business rates at its Swansea store could define the future of the retail brand's entire network.
The department store chain, which went into administration in April, said that the action in South Wales would serve as a test case for similar cases elsewhere in the UK.
Debenhams says its rates bill in Swansea is due to rise by 12% to £1.1m.
They have lodged an appeal against the increase at the local Valuation Tribunal for Wales.
The brand warned that unless more realistic assessments are agreed, Debenhams is likely to have to close more stores, with the result that thousands more workers will lose their jobs.
Since lockdown, the network has already shrunk from 142 to 124 stores with 6,500 staff made redundant, taking the group headcount to around 12,000.
A spokesperson for Debenhams said: “The Swansea hearing is a vital test case, with serious implications for jobs, both locally and across the UK.
"The outcome will go a long way to defining the future of every one of our stores.
"Currently, we have a completely unsustainable situation where rents are going down, but our rates bill is going up.
"We understand the pressures on the Treasury but, unless common sense prevails, the end result of rates hikes will be further store closures and more job losses.
"We are fighting hard to save every store – and every job – we can and the outcome of the Swansea tribunal will go a long way to determining the ultimate size of the business.”
The date of the Swansea rates tribunal is to be confirmed. It is expected to take place in October.
