India has asked France's Dassault Aviation SA to stick to the original price tag for fighter jets or risk losing one of the world's biggest military aircraft deals, the Times of India reported on Tuesday.

Talks on the proposed purchase of 126 Rafale planes have been ongoing for more than three years to resolve differences over pricing as well as local assembly. The deal is back in focus as Prime Minister Narendra Modi visits France this week.

The deal was initially worth $12 billion but is now widely estimated to have jumped to $20 billion, primarily because of the implications of building some of the jets in India.