Actress Priyanka Chopra and American singer Nick Jonas, who themselves became husband and wife earlier this month, were also guests at Udaipur’s City Palace on the banks of Lake Pichola.
Wednesday evening’s actual wedding was set to be a more private affair with around 600 close friends and family, and some politicians, expected to be on the guest list.
There was a high police presence in the south Mumbai area around the Ambanis’ home, which is called Antilia and reportedly cost over $1bn when it was completed in 2010.
Indian newspapers have been abuzz with speculation about the total cost of the wedding. Conservative estimates have put it around $15m while others insist $100m is closer to the truth.
Ambani, 27 and Piramal, 33 got engaged at Lake Como in Italy in September and the high-profile wedding brings together two of India’s biggest industrialist families.
Mukesh Ambani is the chair of oil-to-telecoms conglomerate Reliance Industries. He is worth more than $47bn and recently overtook China’s Jack Ma as Asia’s wealthiest man.