Top CEOs from India and abroad on Wednesday committed to invest Rs. 4,50,000 crores for the Modi government's ambitious 'Digital India' campaign to provide telephony and fast internet for all, with more than half of the promised investments announced by Mukesh Ambani alone.

The Reliance Industries Chairman was joined by top industry leaders like Sunil Bharti Mittal (Rs. 1,00,000 crores), Kumar Mangalam Birla ($9 billion or about Rs. 54,000 crores), and Anil Agarwal (Rs. 40,000 crores) with large investment announcements.

His younger brother Anil Ambani, Chairman of Reliance Group, also announced an investment of Rs. 10,000 crores to expand businesses across digital, cloud and telecom space.

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The launch ceremony of Digital India week by Prime Minister Narendra Modi, at the packed Indira Gandhi Indoor Stadium, was attended by who's who of India Inc, as also top executives of a number of foreign companies, who committed huge investments in creation of infrastructure and setting up of manufacturing units.

The investments announced on Wednesday will lead to creation of 1.8 million jobs, IT and Telecom Minister Ravi Shankar Prasad said at the event.

Reliance Industries Chairman Mukesh Ambani pledged an investment of over Rs. 2,50,000 crores in rollout of wireless broadband infrastructure and manufcture of mobile handsets.

The company is working with leading device manufacturers encouraging them to Make in India smartphones and internet devices at an affordable price, he said.

Bharti group chief Sunil Mittal said his group will invest more than Rs. 1,00,000 crores in the next five years in networks and deeper infrastructure for taking 4G connectivity to the masses, e-health and taking e-education in every village.

The company will also collaborate with various manufacturers around the world to start manufacturing in the country to provide electronic products at the most affordable and reduce the burden of electronics import in this country.

Aditya Birla group, which owns the country's third largest mobile operator Idea Cellular, will invest $7 billion (roughly Rs. 44,481 crores) over the next five years in network roll out, broadband and Wi-Fi deployment, its Chairman Kumar Mangalam Birla said.

Besides, he also announced a $2 billion (roughly Rs. 12,709 crores) investment over the next five years specifically for Digital India plans.