Reliance Industries Chairman Mukesh Ambani's skyscraper residence in Mumbai is the most expensive billionaire home in the world, according to a Forbes list which also includes Indian-origin steel tycoon Lakshmi Mittal's houses in London.

Ambani's 27-story, 400,000-square-foot skyscraper home Antilia named after a mythical island in the Atlantic, tops the Forbes list of the most expensive homes in the world.

"The title of the most outrageously expensive property in the world still belongs to Mukesh Ambani's Antilia in Mumbai," Forbes said adding it is the world's most expensive home "far and away" with construction costs reported between a range of USD one billion to two billion.

The house has six stories of underground parking, three helicopter pads, and reportedly requires a staff of 600 to keep it running.