London world's most expensive city, Mumbai 17th

London: London has been ranked as the world's most expensive city to live and work in, ahead of New York and Hong Kong, according to a UK study that puts Mumbai at 17th.

The only India city on the list of top 20, Mumbai is ranked 17th ahead only of Berlin, Johannesburg and Rio de Janeiro by the UK real estate firm Savills survey that was released on Monday.

It compares the total annual cost of renting both residential and office accommodation per person in some of the world's leading cities.

London is 18 percent more expensive than it was five years ago, and has been ranked at the top of the index since 2014.

The cost of living in the British capital comes to more than double the cost of other English-speaking cities such as Sydney, Los Angeles and Chicago.

"The highest ranking global cities, London and New York, are also the most expensive for businesses and workers to occupy... World cities can become a victim of their own success when rents rise to the point where affordability becomes an issue," said Yolande Barnes, head of Savills World Research.

"The productivity of cities and their value to global businesses clearly has a pronounced effect on demand and hence rental costs," she said.

Her research found that accommodation for the average Londoner calculated as a total of housing and office rental costs - comes to 80,700 pounds a year, compared to 79,600 pounds in New York and 73,800 pounds in Hong Kong.

Savills puts together its study as an indicator for companies of the cost of doing business in different world cities.