Kardashians in India for billionaire wedding gala
Ambani's youngest son Anant and fiancee Radhika Merchant, both 29, will tie the knot over the weekend in the financial capital Mumbai following months of pre-marriage parties that have set a new benchmark in matrimonial extravagance.
Earlier celebrations included a European cruise for 1,200 guests, a purpose-built Hindu temple at the Ambani family's ancestral home and private performances by R&B star Rihanna and Canada's Justin Bieber.
The Kardashians are the latest in a long line of famous foreign VIPs to make an appearance.
Elder sister Kim shared an Instagram story showing her car mobbed by Indian photographers shortly after her arrival and both siblings receiving flower garlands from staff at their luxury hotel.
Former British prime ministers Boris Johnson and Tony Blair were also spotted by reporters arriving at Mumbai airport ahead of the party beginning later on Friday.
In June, the couple embarked on a four-day Mediterranean cruise, where singer Katy Perry performed at a masquerade ball at a French chateau in Cannes.
The Backstreet Boys, US rapper Pitbull and Italian tenor Andrea Bocelli also provided entertainment.
Guests at earlier galas have included Facebook founder Mark Zuckerberg and former US president Donald Trump's daughter Ivanka, along with a who's who of India's sporting and entertainment worlds.
This week's opulent celebrations are set to raise the bar, with even more celebrities, politicians and global business elites jetting into the monsoon-hit megacity of Mumbai.
Former US presidential candidate Hillary Clinton, boxing star Mike Tyson and actor John Cena are among the other names rumoured to be attending.
Anant's father Mukesh is chairman of Reliance Industries, a family-founded conglomerate that has grown into India's biggest company by market cap.
The patriarch is the world's 11th richest person with a fortune of more than $113 billion, according to Forbes, and is no stranger to making a statement when it comes to family marriages.
He held the most expensive wedding in India to date for his daughter in 2018, which reportedly cost $100 million and saw US singer Beyonce perform.
Ambani is also a key ally of India's right-wing Hindu nationalist leader, Prime Minister Narendra Modi.
He inherited a thriving industrial enterprise spanning oil, gas and petrochemicals and grew it into a commercial behemoth with lucrative interests in retail, telecommunications and an Indian Premier League cricket team.
His 27-floor family home Antilia is one of Mumbai's most prominent landmarks, reportedly costing more than $1 billion to build and with a permanent staff of 600 servants.
Merchant is the daughter of well-known pharmaceutical moguls.