In the Property Rich List 2009, an annual survey of priciest areas in the UK compiled by real estate website Zoopla, Kensignton Palace Gardens has retained its title as 'Britain's Most Expensive Street' with an average house price of about 22 million pounds.
Mittal, whose net worth has fallen by 16.9 billion pounds over the past one year to 10.8 billion pounds, own three houses on this street.
"Known as Billionaire's Row for its list of well-heeled residents including three homes owned by the country's richest family, the Mittals, the residents of this tree-lined avenue may well not be celebrating the fact that each home on this street has lost almost five million pounds (18.4 per cent) in value over the past 12 months," Zoopla said.
On Sunday, Mittal was named as Britain's richest person for the fifth straight year in the annual ranking of 1,000 richest persons in the UK compiled by the Sunday Times newspaper.
This is despite Mittal emerging as the biggest loser of wealth over the past one year and the decline in his net worth accounting for over one-tenth of the total loss of 155 million pounds in the cumulative wealth of all the 1,000 persons.
Commenting on the Property Rich List 2009, Zoopla CEO Alex Chesterman said, "Despite the current economic climate much of the country's wealth remains tied up in the property market and whilst average house prices are down across the board last year, there still remain some pretty eye-watering numbers in this year's Property Rich List."
The survey also named Kensington in West London as the UK's most expensive address, "topping both the postcode ranking with average property prices in (Kensington) W8 of over 1.3 million pounds and as home to the country's most expensive street, Kensington Palace Gardens where the average pad will set you back a staggering 22 million pounds."
In a separate survey last year, Kensington Palace Gardens was ranked as the world's fourth most expensive street.
The list compiled in August 2008 by Wealth-Bulletin, a UK-based online news and analysis provider for global wealth management industry, had put the price tag of Kensington Palace Gardens at $77,000 per square metre.
In July last year, Mittal is said to have purchased a 70 million pound house for his daughter Vanisha on this street -- close after a world record 117-million-pound mansion bought for his son Aditya and the third for the family in the same area.
Mittal had purchased his first house on the Billionaire's Row for 57 million pounds more than four years ago.
The street has been home to a number of celebrities even before Mittals came here. Late Princess Diana once lived in this street and its current residents include Chelsea Football
Club owner Roman Abramovich. Kensington Palace Gardens is a private avenue lined with trees and dotted with foreign embassies.