Retailers are being threatened with the prospect of further significant business rate rises when new levels are implemented next April.

Those rates will be based on this September's Retail Price Index (RPI) inflation measure, which is expected to be above 4%, leading to rate increases of up to 22% for some stores.

The British Retail Consortium (BRC) called on the government to adopt a more stable and predictable method of calculating rates, and one which would not undermine retailers' ability to maintain and create jobs.

BRC director general Stephen Robertson suggested using the lower Consumer Price Index, or a 12-month average RPI rate that would "help iron out inflation volatility".

Meanwhile, Association of Convenience Stores (ACS) chief executive James Lowman has called for a total freeze in rate increases for 2011.

"The burden of business rates is one of the most significant cost pressures on retailers we urge government to think carefully about the burden of increasing the rate again," he said.

Some retailers will have to pay the new rate, to be announced next month, at the same time as they settle deferred payments from 2009, which could lead to cash flow problems and further empty stores on high streets.

According to research from the Local Data Company (LDC), store vacancy levels in shopping areas rose from 10.5% to 13% in the past year.

LDC business development director Matthew Hopkinson said that any increase to the cost of running a business would be "another nail in the coffin" for shops and that raising costs will lead to a "higher number of closures".