More than a third of Wi-Fi hotspots in the City and Docklands areas of London are unprotected by encryption, putting users' data at risk, security experts have warned.

Security firm Kaspersky Lab conducted research comparing 400 Wi-Fi hotspots in the City and the Docklands area surrounding Canary Wharf with 400 across the rest of London.

It found that across the capital, 31 percent of networks were still unprotected by encryption. But the figure for the City showed levels of encryption were worse, with 35 percent of hotspots unprotected.

In a report on the research, Kaspersky notes that the City and Docklands areas made up London's main business district, where many major financial institutions and media corporations have their headquarters. "These are the very organisations that could be targeted by hackers and fall victim to the theft of commercial information."

The figures do show progress from last year, when half of all London hotspots tested by Kaspersky were unprotected, as were 40 percent of those in the City.

But the report notes that while encryption levels have gone up slightly, the total number of Wi-Fi hotspots has "more than doubled."

It warns: "In the end, the new networks aren't that much different from the older ones, and clearly not all potential threats - which have been recognised for years now - are taken into consideration when these networks are set up."