With $4.1 billion (2.9 billion British pounds) in accumulated rent debts, roughly two-thirds of major U.K. retailers face legal action for unpaid rent by the end of June, potentially leaving thousands of brick-and-mortar stores in peril. Without government intervention, retailers could see a "tsunami of closures," London-based British Retail Consortium (BRC) said Sunday in a press release.

In Spring 2020, the U.K. government issued a code of practice over outstanding rent payments, while curbing aggressive debt collection practices until June 30.

Government officials plan to address commercial rent. "The government is considering responses to a call for evidence on commercial rents and how to best to support businesses; an announcement on next steps will be made in due course," a business department spokesperson said, according to BBC News.

The BRC noted that "80% of tenants said some landlords have given them less than a year to pay back rent arrears accrued during the pandemic." The press release also cited that one in seven shops are empty and that the number is expected to rise.

It is unclear how steep the fallout will be if action isn't taken by June 30. Melanie Leech, head of the real estate group British Property Federation, disputed the threat to the retail sector.

"It is disappointing to see the BRC failing to recognize that the vast majority of property owners and tenants have already reached agreement on rent," Leech told the Financial Times.

U.S.-based consulting firm McKinsey & Co. posted on Twitter that the number of Brits who said they won't shop online has dropped during the pandemic, from 25% to 15%.

The data from the BRC comes amid a sharp rebound in retail sales in April. According to the Office of National Statistics, retail sales soared 9.2% and sales of clothing were up by nearly 70% compared to March.

A press release on May 21 from the IHS/Markit Purchasing Managers' Index cited that the private sector signaled the "fastest output growth for more than two decades."