The success of Anil Ambani's ambitious defence plan will depend partly on whether he can persuade government officials and international partners that he can build sophisticated equipment and partly on whether the PM can get India's notoriously slow procurement process to work, say Paritosh Bansal, Sanjeev Miglani and Promit Mukherjee.
The contract would give a big boost to India's $150 billion nuclear power programme, and a broader push to curb greenhouse gas emissions.
This would make India the world's second-biggest nuclear energy market after China
The decision ahead of Japanese Prime Minister Shinzo Abe's visit beginning on Friday gives Tokyo an early lead over China.
Japan offers India soft loan for $15 bln bullet train in edge over China
Politicians appeal to key groups of voters like farmers or the poor by keeping prices low and ignoring theft, prompting scepticism about whether states will agree to any package that forces tariff hikes.
China seeks to cash in on Modi's vision of modernising a creaking train system that 25 million people use daily
Modi has made nuclear power a key element of his clean energy strategy
Irked by India's status as the world's biggest arms importer, Modi wants to build an advanced defence industry
India will issue a new decree this week for land purchases that has stirred disquiet across the country
China has invested millions in Sri Lankan infrastructure.
Under a 2010 nuclear liability law, nuclear equipment suppliers are liable for damages from an accident, which companies say is a sharp deviation from international norms
Critics say Modi scores high on oratory but has delivered on few of his election campaign promises.
Xi and Modi met soon after their arrival at a summit of the BRICS group of emerging powers. Xi said the two countries should join hands in setting global rules and suggested he attend the November meeting of the 21-nation APEC in Beijing, as well as take part in Chinese-led regional initiatives.