On England’s high streets, non-essential shops will start to emerge from a 12-week hibernation on Monday; some countries are further ahead. As well as being a key step in reviving economies, reopening shops will provide retailers with some revenues out of which to pay their landlords. Yet a potentially nasty sting in the tail of the recovery still lurks in the form of huge volumes of unpaid commercial property rents.

In the US, nearly half of commercial rents went unpaid in May. The vacancy rate at shopping malls has hit an all-time high. In the UK, where the government has introduced a temporary ban on the eviction of tenants for non-payment of rents, many landlords have said their own income has fallen by as much as two-thirds. Two of the biggest shopping centre owners, Hammerson and Intu, have seen their share prices collapse. Intu, which was already heavily indebted before the crisis, received just 29 per cent of the rent it was due for the second quarter of the year.

Landlords do not usually elicit much compassion, but the predicament of the commercial real estate sector deserves attention — not least because it could very easily become a problem for the wider economy. Banks, pension funds and life insurers are among the groups holding commercial mortgages and exposed to any potential defaults. Property companies are not as leveraged as they were before the financial downturn in 2008 but concerns are rife that another crisis is looming.