Today’s quarterly rent payment will be the harshest for at least 18 years, the British Retail Consortium has warned.

The BRC urged landlords to show more flexibility on rents, as the first few months of the year have seen low levels of consumer spending.

This has been compounded by the recession and follows the worst December sales performance since the BRC’s Retail Sales Monitor has recorded in its 14 years.

The BRC said some landlords have offered flexibility on existing leases, but it calls on all landlords to show willingness to switch to monthly terms.

BRC director general Stephen Robertson said: “A dismal Christmas for many retailers and following the year’s lowest spending months has meant the toughest quarter day since the early 1990s. A thriving retail sector is essential for the health of landlords and the wider UK economy. Boarded up shops are becoming commonplace. An unrealistic payments regime can only increase the pressure on hard-pressed retailers and the jobs they support.”

The BRC’s How To guide to help retailers ask landlords for new terms has been downloaded from the BRC website over 50,000 times since the start of 2008.

According to Experian, by the end of this year 140,000 shops will be vacant and 200,000 retail jobs will have been lost.