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Facebook valued Jio Platforms - part of billionaire Mukesh Ambani-led Reliance Industries group - at Rs 4.62 lakh crore.
After the deal, Reliance Jio Infocomm will continue to be a wholly-owned subsidiary of Jio Platforms.
The partnership assumes a "special significance for India in the wake of the severe disruptions caused by the coronavirus pandemic in the Indian - and the global - economy", Reliance Jio said. In a post-COVID-19 era, "comprehensive digitalisation will be an absolute necessity for revitalisation of the Indian economy".
The companies will "work closely to ensure that consumers are able to access the nearest kiranas who can provide products and services to their homes by transacting seamlessly with JioMart using WhatsApp", Reliance Jio added.
"Over the past few years, Facebook, WhatsApp and Instagram have become household names in India. WhatsApp, in particular, has entered our people's daily vocabulary in all the 23 official languages of India," Reliance Industries chairman Mukesh Ambani said. "WhatsApp is not just a digital application, it has become aapka, aur hum sabka, pyaara dost," he said in a video statement.
WhatsApp has 400 million users in India - its biggest market, reaching nearly 80 per cent of smartphone users in the country.
Jio Platforms, Reliance Retail and WhatsApp have also entered into a commercial partnership agreement to further accelerate Reliance Retail's New Commerce business on the JioMart platform using WhatsApp to support small businesses on WhatsApp, the company said.
Jio said the investment values Jio Platforms among the top five listed companies in India by market capitalisation, within just three and a half years of launch of commercial services "validating Reliance Industries' capability in incubating and building".
disruptive next-generation businesses, while delivering market defining shareholder value.
Reliance Jio, the fast-growing telecom carrier controlled by billionaire Mukesh Ambani, began operations in late 2016. It provides telecom and digital services under brand Jio, and a connectivity platform to more than 38.8 crore subscribers.
Reliance Industries is the country's most valued company, whose activities span hydrocarbon exploration and production, petroleum refining and marketing, petrochemicals, retail and digital services.