CHRONOLOGY - Twists and turns in the India-U.S. nuclear deal

Indian and U.S. national flags flutter ahead of the visit of U.S. President George W. Bush in New Delhi in this February 28, 2006 file photo.

Reuters - U.S. Senate Majority Leader Harry Reid has scheduled a vote for Wednesday evening on a deal to end the three-decade ban on U.S. civilian nuclear trade with India.

Here is a timeline of some key developments over the past three years:

* July 2005: Prime Minister Manmohan Singh and U.S. President George W. Bush agree in principle to a landmark civilian nuclear cooperation deal. It reverses 30 years of U.S. policy opposing nuclear cooperation with India because it developed nuclear weapons and never signed the Non-Proliferation Treaty, or NPT.

* March 2006: Bush pays a three-day visit to India during which the two countries agree on India's plan to separate its civil and military nuclear reactors, a key requirement for the deal to go through.

* Dec. 2006: U.S. Congress overwhelmingly approves the deal. Three other approvals -- from the 45-nation Nuclear Suppliers Group, the International Atomic Energy Agency (IAEA) and a second time by Congress -- are still needed before nuclear transfers to India can actually take place.

* Dec. 2006: Bush signs the law approved by Congress, which makes changes to the U.S. Atomic Energy Act. Analysts say the pact could be fully approved in roughly six months.

* July 2007: The two countries announce finalisation of the deal after months of tough negotiations on a bilateral pact. India had objected to what it said were new conditions in the agreement unacceptable to it.

* Aug. 2007: Text of the bilateral pact, called the 123 agreement, is unveiled simultaneously in both countries. Indian analysts say it meets most of New Delhi's demands, but communist allies of the government coalition threaten to withdraw support over the pact, saying it compromises India's sovereignty. Singh defends the deal as crucial to India's prosperity.

* July 9, 2008: India's left withdraws support for the government, and calls for a vote of no confidence. India submits a draft nuclear safeguards accord to the IAEA governors for approval, despite earlier assurances it would wait to do so until after winning the confidence vote.

* July 10: Agreeing to demands from the left, Singh calls for a vote of confidence in his government.

* July 22 - Singh wins confidence vote.

* Aug. 1 - IAEA governors approve India nuclear inspections plan.

* Sept. 6 - The 45 nuclear supplier states approve the U.S. nuclear deal, clearing a key international hurdle.

* Sept. 27 - U.S. House of Representatives approves deal.