The mayor of London, Sadiq Khan, is poised to name a “night tsar” after a spate of closures of clubs and other late-night venues that has prompted alarm about the city’s future as a 24-hour city.

The identity of the tsar will be made public next month, and a report by the mayor-appointed “night time commission” published by the end of the year. The commission will propose steps to promote the night-time economy as “a key driver of economic and cultural regeneration, and a magnet for domestic and international visitors”.

According to a recent study by London First, the capital’s night-time businesses contributed up to £26.3bn to the UK economy in 2014, forecast to rise by £2bn by 2029. But behind the upbeat tone of the report, club and bar owners are voicing growing concern about their businesses, which they say are being threatened by bureaucracy and the pace and scale of development in London.

In the past five years, London has lost half its nightclubs and more than 40% of its music venues. Last month, one of the country’s best-known nightclubs, Fabric, lost its licence after two drug-related deaths. The closure was “a miserable day for London’s clubbing landscape”, according to the Ministry of Sound.

Earlier this year, Passing Clouds, a live music and community venue in east London, closed after the building’s lease was sold to “property developers seeking to cash in on the huge popularity of Dalston, which we ourselves were instrumental in helping to establish”, said Gudrun Getz, its events manager. “Every venue owner I’ve spoken to is worried they’re going to be next on the chopping block,” she told the World Travel Guide.

The roll call of closures includes Cable, a 1,300-capacity club under railway arches in London Bridge, which in 2013 was forced to make way for station redevelopment; Turnmills, which became an office block; and the Vibe Bar in Brick Lane, which closed in 2014 due to “excessive and unreasonable restrictions on our activity”. The Coronet in south London recently won a year’s reprieve but is expected to close in January 2018 as part of a shopping centre redevelopment.

Club owners and advocates of London’s night-time economy blame restrictive licensing laws, aggressive property development and growing complaints from new residents.

“What’s frustrating about the UK is that we don’t actually see that the night-time economy helps make places more attractive to a highly educated, very mobile, creative workforce that creates a huge number of new jobs and businesses wherever they choose to go,” said Rohan Silva, the founder of start-up workspace and cultural centre Second Home.

“British policy makers don’t understand the relationship between the night-time economy and our cities being places that talented people want to live and work in.”

London’s mayor and his new night tsar will address these issues, says City Hall. Better protection for music venues and nightclubs will be put in place and the mayor will work with developers to find new sites. A new “agent of change” principle means that the onus will be on developers to take steps such as soundproofing new residential properties in areas where music venues or nightclubs are already established. Likewise, if a nightclub opens in a residential area, it will be responsible for safeguarding residents’ peace.

Paris, Berlin, Amsterdam, Zurich and Toulouse already have “night mayors” but, said Marion Roberts, professor of urban design at the University of Westminster, “you have to be very careful about making comparisons between London and other European cities”. London’s population is almost three times that of Berlin and four times that of Paris, she pointed out. “New York or Tokyo are more accurate comparators.”

Roberts hopes the night tsar will encourage new kinds of night-time activity in London, such as markets, gallery openings, film clubs and classical music concerts, as well as clubs. Londoners want relaxed, quirky and experimental offerings, she said.

According to Silva, “it’s striking how few things there are to do at 1am or 2am. We’re nothing like a 24-hour city.” He opened his bookshop Libreria through the night to mark the start of the night tube in August and was astonished when thousands of people flocked there.

He also cited the popularity of the Institut Francais’ all-night philosophy sessions, and the Shuffle festival in Mile End, “where there was poetry at 3am and science workshops at 4am, and it was packed all night”.

Changes in working patterns were fuelling demand for more flexibility in people’s lives, he said. “By the end of 2018, we’re expecting there to be more freelancers and self-employed than there are people working in the public sector.

“There have been profound shifts in the way we work, freeing people from the tyranny of nine to five. It’s creating more expectation that cities like London should cater for different lifestyles.”

Meanwhile, an appeal against Fabric’s loss of licence will be heard next month, and many clubbers, club owners and champions of the night-time economy will be watching closely. “It will be a signal,” said Silva. “London is facing a big test of its resolve post-Brexit to be attractive to global people who can choose to be anywhere they want to be. We need all the positive messages we can muster.”