The text of the agreement, which took two years to complete, tackles controversial issues such as the reprocessing of nuclear material.
The deal has also come under criticism from some Americans who worry it will stymie US anti-proliferation efforts, especially in Iran.
The agreement itself, by which the US will share nuclear technology with India, has come under criticism, especially from Pakistan, which has said in the past the deal would "enable India to produce significant quantities of fissile material and nuclear weapons".
India has fought three wars with Pakistan in the past 60 years, both countries have developed nuclear weapons and in 1998 carried out tit-for-tat nuclear detonations.
The Indian government insists its nuclear relationship with the US will not alter the balance of power in the region.
"The deal actually means the technology restrictions that India has been subjected to since 1978 have been lifted," Krishnaswami Subrahmanyam, nuclear and security expert, told Al Jazeera.
"India in future will have access to nuclear technology and all other high technologies available in the rest of the world, and there will be no technology denial regime as far as India is concerned."
The text of the US-India agreement explicitly forbids the use of any transferred nuclear material for military purposes.
"Nuclear material, equipment and components so transferred shall not be used by the recipient party for any nuclear explosive device, for research on or development of any nuclear explosive device or for any military purpose," it said.
"In essence, India retains the right to test and the US has the right to respond"
C Uday Bhaskar,
Institute for Defence Studies, New Delhi
The US Congress approved legislation in December that allowed US exports of civilian nuclear fuel and technology to India for the first time in 30 years, a move intended to reverse sanctions on India for its nuclear tests.
The operating agreement goes even further, allowing India to reprocess spent fuel under safeguards by the International Atomic Energy Agency (IAEA), the UN nuclear watchdog.
C Uday Bhaskar, from New Delhi's Institute for Defence Studies, said the agreement "respects the distinctive concerns that on nuclear issues that both sides".
"It's a very fine balance. In essence, India retains the right to test and the US has the right to respond," he said.
"There's no direct reference to a test. But the allusion is there. It allows a positive interpretation for both sides."
The US Atomic Energy Act calls for the US president to suspend nuclear co-operation when a country tests an atomic weapon.
But the text released on Friday makes no direct mention of testing and appears to sidestep the issue.
"The parties agree to consider carefully the circumstances that may lead to termination or cessation of cooperation," said the statement.
The India-US deal runs for an initial term of 40 years but can be terminated by either party before that with a year's notice and can be extended by 10-year periods.
The whole accord still has to win the approval of the US Congress and the Indian parliament.