The move is the first sign of change at Ambani's empire after the billionaire last year said his children would have significant roles in the business, adding Reliance was "in the process of effecting a momentous leadership transition."

Here are details about Ambani's three children who are expected to have greater say in India's biggest conglomerate valued at around $200 billion.

AKASH AMBANI, 30

Akash, Ambani's elder son, joined the leadership team at the group's telecom unit, Reliance Jio, in 2014, soon after completing his graduation in economics from Brown University.

As a non-executive director, he worked closely on the company's strategy and growth plans that made Jio India's biggest telecom operator with more than 400 million subscribers. He will now be the chairman of the telecom unit, Reliance said Tuesday.

Akash has been closely involved in product development and employee engagement to bring a "young and vibrant culture", the company says. An avid cricketer, he also plays a key role in the management of Mumbai Indians, a Reliance-owned team in IPL, the world's richest cricket league.

Akash was also part of a team that brokered a $5.7 billion investment in 2020 by Meta Platforms in a Reliance unit, Jio Platforms.

In 2019, he married Shloka Mehta, the daughter of a wealthy diamond merchant.

ISHA AMBANI, 30

Isha is Akash's twin sister and already tasked with driving the company's retail, e-commerce and luxury plans. Reliance is also India's biggest bricks-and-mortar retailer, with plans to expand swiftly into e-commerce to take on giants like Amazon.

She is also involved in expanding Reliance's presence in fashion through the company's Ajio e-commerce app as well as Reliance's partnerships with top international brands.

Isha has a business management degree from Stanford. Fortune magazine last year referred to her as "Heiress on Duty" while ranking her the 21st most powerful woman in India.

She is working closely in conceptualising a new Reliance mall, including how the company pitches the highly sensitive placement of rival luxury brands next to each other, Reuters has reported.

In 2018, Isha married Anand Piramal, the son of a billionaire industrialist with interests in real estate and pharma.

ANANT AMBANI, 27

Anant is Ambani's youngest son who is focussing on the conglomerate's new energy business, a key area of investment for Ambanis.

Reliance is vying to be at the forefront of Prime Minister Narendra Modi's ambition to ramp up green energy capacity.

Reliance has major expansion plans to diversify into clean energy projects, including solar and green hydrogen.

Anant has in the past addressed audiences, along with Akash and Isha, at company events. Anant graduated from Brown University in 2017.

(Reporting by Abhirup Roy and Aditya Kalra, Editing by Alexandra Hudson)