After months of lavish celebrations, the wedding ceremony of the son of Asia’s richest man is finally under way in the Indian city of Mumbai.

Anant Ambani, son of Reliance Industries chairman Mukesh Ambani, is tying the knot with Radhika Merchant, daughter of pharma tycoons Viren and Shaila Merchant.

The four-day extravaganza is the final stop in a string of elaborate parties the family has hosted since March, which have featured performances by popstars including Rihanna and Justin Bieber.

Reality TV star Kim Kardashian, and former UK PMs Tony Blair and Boris Johnson, were among the international guests. Also spotted was US wrestler and actor John Cena, who was seen hugging and congratulating relatives of the host.

Key roads in Mumbai are being sealed off for several hours a day until the festivities end on Monday.

Social media is awash with updates on the wedding, with people sharing minute-by-minute details of Bollywood stars and celebrities arriving.

But the extraordinary opulence has also led to backlash – city dwellers have complained the road closures have worsened traffic snarls caused by monsoon flooding, while others have questioned the ostentatious display of wealth at the seemingly never-ending celebrations.

Mukesh Ambani, 66, is at present the world’s 10th richest man with a net worth of $115bn, according to Forbes. Reliance Industries, founded by his father in 1966, is a massive conglomerate that operates in sectors ranging from petroleum and retail, to financial services and telecoms.

Anant Ambani is the youngest of his three children, all of whom are on the board of Reliance Industries. The 29-year-old is involved in Reliance’s energy businesses and is on the board of Reliance Foundation.

The Ambanis have not revealed how much this wedding is costing them but wedding planners estimate they’ve already spent anywhere between 11bn and 13bn rupees [$132m-$156m]. It was rumoured Rihanna had been paid $7m (£5.5m) for her performance, while the figure suggested for Justin Bieber is $10m.

One unnamed executive at Reliance claimed the event was a “powerful symbol of India’s growing stature on the global stage” in a note shared with reporters.

But opposition politician Thomas Isaac said it was “obscene”.

“Legally it may be their money but such ostentatious expenditure is a sin against mother earth and (the) poor,” he posted on X.

On Friday, the groom set off from his residence in a luxurious red car covered in strings of white flowers, as joyful guests danced around it.

A convoy of cars, also decorated with flowers and carrying family members, followed him with music and cheers.

The grand procession, known as the baraat, culminated at the wedding venue – a convention centre owned by the Ambanis – where several Bollywood stars joined in another round of singing and dancing.

Reports say the bride and groom will exchange garlands to kick off the wedding. The pheras – the main wedding ritual of the couple walking around the sacred fire seven times – is set for 21:30 (1600GMT).

Guests will reportedly bless the newly-weds in a formal ceremony on Saturday – followed by a grand party where unconfirmed reports say pop stars Drake, Lana Del Ray and Adele are likely to perform.

Pictures and videos of Kim Kardashian, who is in the city with her sister Khloé Kardashian, are being widely shared online.

Reports say the sisters have brought a team of stylists, including celebrity hairstylist Chris Appleton, along with a group of producers to capture every detail of their trip.

Former Indian president Ram Nath Kovind, British High Commissioner to India Lindy Cameron, and US Ambassador to India Eric Garcetti are also in the city to attend the wedding.

Rajan Mehra, CEO of air charter company Club One Air, told Reuters that the family had rented three Falcon-2000 jets to ferry wedding guests to the event.

“The guests are coming from all over and each aircraft will make multiple trips across the country,” he said.

The wedding festivities began in March when the family held a three-day pre-wedding party in their home state of Gujarat.

Among the 1,200 guests to attend that celebration were Meta’s Mark Zuckerberg and Microsoft’s Bill Gates.

The party started with a performance by Rihanna on the first night. Diljit Dosanjh, the first Punjabi singer to perform at Coachella, took the stage on the second night, while rapper Akon closed the show on the final day of celebrations.

In June, the Ambanis organised another pre-wedding celebration, this time, a luxury cruise from Italy to France. The Backstreet Boys, Katy Perry and Pitbull performed for the 800 guests, which included Bollywood stars and cricketers.

Money was also lavished on constructing 14 temples inside a sprawling complex in Jamnagar to showcase India’s cultural heritage and provide a backdrop for the wedding. As part of the celebrations, the Ambanis hosted a mass wedding for 50 underprivileged couples.

On Wednesday, the family hosted a bhandara – a community feast for underprivileged people.