India's roughly $150 billion outsourcing sector generates about three quarters of its revenue from the United States.
Critics say the programme, launched 10 months ago in India in collaboration with operator Reliance Communications, violates principles of net neutrality
Poor disclosure among India-listed firms is a turnoff for foreign investors.
The tax would create a single market in India for the first time.
IndiGo was set up in 2006 by businessman Rahul Bhatia and Rakesh Gangwal, a former CEO for US Airways Group.
PM said he admires German leadership in clean energy and commitment to combating climate change.
India and Germany signed a deal on Monday to fast-track business approvals.
India's tax officials, long the scourge of foreign investors, are under government pressure to avoid aggressive claims against overseas funds.
The rupee has fallen more than 2 per cent against the dollar since the yuan devaluation
India's mutual funds are seeing a surge in stock investments from the hinterland as growing ranks of provincial retail investors help drive a two-year long rally.
An estimated $344 billion has been illegally removed from the Indian economy between 2002 and 2011
The government said on Wednesday a consensus was needed quickly to pass a business-friendly land reform law
The wholesale food index rose 2.88 per cent year-on-year.
India imposes restrictions on how much money its citizens and companies can invest abroad
Investor lobbies and tax lawyers estimate the bill for international funds and banks could be as high as $8 billion
The United States wants India to wait for a final nuclear deal between Tehran and world powers before actively engaging with Tehran.
India will be able to manage potential inflationary pressures if forecasts of sub-par monsoon
Sebi has long struggled with balancing the needs of small investors and those of the market.
The move will likely attract more retail investors.
IMF MD Christine Lagarde hailed the government's latest Budget.