Sadiq Khan has admitted central London will not be “anywhere near” pre-Covid levels for months to come as he prepares to survey businesses about their back to office plans.

The London mayor told City A.M. in an exclusive interview – released tomorrow in full – that office and public transport social distancing rules meant central London will only have a fraction of its previous footfall, and this would lead to many businesses going bust without further government assistance.

Large sections of central London – including the Square Mile – remain relatively empty, despite the government saying last month that it was safe to return to the workplace.

Recent analysis revealed just 17 per cent of people have returned to work in the UK’s 63 largest cities, with the slow recovery in footfall imperiling thousands of bricks and mortar companies, especially in the leisure, retail and culture industries.

Fears about the economic damage have led to a growing chorus of business bodies, lobby groups and MPs to call for people to return to their workplaces in order to stoke High Street spending.

Khan has come under pressure from some to get more people back on the Tube as a part of this push as passenger numbers are still down 70 per cent from a year ago.

However, the mayor told City A.M. it was just not realistic to expect a return to normality any time soon as government guidelines still force people to stay between one and two metres apart in offices and on public transport.

“The reality is that unless we have a vaccine for the virus we aren’t going to get anywhere near 100 per cent for some time – that’s just a reality unless you’re reckless,” Khan said.

“We think on the Tubes a safe number at any one time is about 25 per cent [capacity] and a safe number on the buses is 40 per cent.”

It comes as City Hall is launching a survey asking London business owners how much of their workforce can safely return to their workplace under current government guidelines.

Khan said this could provide clarity on predicted High Street footfall for the short-to-medium term future, while adding that it will also show the need for further government intervention.

“The reality is that in some sectors like culture, hospitality, leisure and retail they need 100 per cent capacity to survive,” he said.

“What the government should be doing is continuing support for those sectors that can’t operate at 100 per cent in the short-to-medium term otherwise they’ll go bust.”

It was reported widely this week that the government was about to launch a “back to work” drive in an attempt to stimulate spending in High Streets across Britain.

However, by Thursday the drive was reported to have stalled and the Prime Minister’s spokesman then said “there’s never been a back to work campaign” and that it was a “press partnership campaign with regional and local media”.

The government’s messaging around whether it unambiguously supports people going back to the office has also been unclear, with some ministers being more cautious than others.

John Dickie, director of strategy and policy at lobby group London First, said the capital’s “future prosperity relies on getting more people back to their workplaces more often”.

“Government needs to end its messaging muddle,” he said.

“Businesses and their employees need clear, consistent, and unambiguous messaging from central and London governments, supporting the safe return on public transport.”

Federation of Small Businesses chair Mike Cherry called for further support for businesses after the government’s furlough scheme ends at the end of next month.

“Many smaller businesses in central London were already financially squeezed pre-Covid due to high rents, business rates and employment costs,” he said.

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“Many will struggle to come out the other end of this successfully without further support to help them through this extraordinary situation.”

A government spokesperson said: “Our extensive Safer Working guidance, developed in consultation with business and trade unions, allows employers to make their workplaces Covid-secure so that employees can safety return to the workplace.

“We are seeing a growing trend of more people returning to the office, including within Central London, and we expect this to continue.”