MUMBAI, Aug 28 (Reuters) - Reliance Industries' retail unit is attracting "strong interest" from other top investors after raising $1 billion from Qatar Investment Authority, its billionaire chairman Mukesh Ambani said on Monday.

Reliance Retail, which aims to list on the stock market, raised $1 billion from Qatar Investment Authority at a $100 billion valuation last week, three years after a wave of fundraising where the unit attracted investors such as KKR, Silver Lake and TPG.

"In less than three years, the valuation of Retail has almost doubled, notwithstanding the intervening COVID-19 pandemic," Ambani, Asia's richest person, said during the company's annual general meeting.

"Several marquee global strategic and financial investors have shown strong interest in Reliance Retail," he said, adding he would share progress about them "in due course".

Ambani said in 2019 that the group planned to list the retail business in five years.

Led by Ambani's daughter Isha, the retail arm includes e-commerce operations and outlets selling electronics, clothing and food products, a consumer goods business and international partnerships with brands like Burberry, Pret A Manger and Tiffany.

Reliance also said on Monday that Ambani's three children, including Isha Ambani, will join the board of parent Reliance Industries.

Reliance Retail has invested more than $10 billion in the last two years and opened 3,300 new stores last year, Isha Ambani said.

Since last year, Reliance has been expanding its consumer business by acquiring dozens of small grocery and non-food brands as it targets building a consumer business generating annual sales of $6.5 billion with five years to challenge foreign giants like Unilever.

It also revived a local cola brand with plans to use its vast retail network, slash prices and tap nationalist sentiment to challenge U.S. beverage giants Coca-Cola and PepsiCo in a key market.

Talking about its consumer brand, Isha Ambani said the company was scaling it up "further in India, and has also started work to take it global, starting with Asia and Africa." (Reporting by M. Sriram; Editing by Aditya Kalra and Susan Fenton)