NEW DELHI: India will become a $4-5 trillion economy in a very short period of time, London-based economist Lord Meghnad Desai said today.The size of Indian economy at present is $2 trillion."Imagine that even at 7 per cent annum the India economy will double every 10 years and if it grows at 10 per cent that will be even faster. This is going to become $4-5 trillion economy in a very very short time," Desai said at the first edition of international real estate expo (IREX) here.Stating that India and Indians are getting prosperous, confident and also becoming global, he said Indians are investing money and buying properties across the world.Foreigners are also coming to work here and they want to buy property, he added.Desai said the world thinks about India positively with great confidence and also seek business opportunities."Even as recently as 1991 when Manmohan Singh (former Prime Minister) began the liberalisation programme, the danger was that foreigners are going to come and roll over us. There is no such danger now," Desai said.IREX Director Vimal Anand said about 45 exhibitors are participating in the 3-days exhibition, targeted at high net worth individuals."We are expecting 5,000 people to visit this exhibition. We also hope some transactions to conclude," he said.In the exhibition, real estate developers and property marketing companies from US, UK, Europe, UAE, Australia and Sri Lanka are taking part such as Damac, Emaar Properties, Sotheby's International and Trafalgar.Indian builders participating in the event include DLF, Tata Housing and Mahindra Lifespaces.