India and the United States have broken an impasse standing in the way of civil nuclear trade, Indian media reports.
The breakthrough comes as Obama and Indian Prime Minister Narendra Modi met in New Delhi.
The reports said that the pair had ironed out differences on the liability of suppliers to India in the event of a nuclear accident and the United States had dropped its demand to be able to track the whereabouts of nuclear material supplied to India.
US President Obama was given an elaborate welcome at the country's presidential palace in New Delhi.
He walked in his socks to place a commemorative wreath honouring the father of India's independence movement, Mahatma Gandhi.
Tomorrow, Mr Obama was to be the guest of honour at India's Republic Day festivities, making him the first US president to attend the anniversary of the enactment of country's democratic constitution.
Barack Obama has arrived in India with his wife Michelle for a symbolic three-day visit of the country.
In a break from protocol, the US President and the First Lady were met on the tarmac by Prime Minister Narendra Modi.
The two leaders hugged warmly before the group posed for photographs.
Just a year ago, relations between the two countries were at an all-time low when a diplomatic row broke out over allegations an Indian diplomat in the US exploited her housekeeper - leading to the abrupt resignation of the US ambassador from India.
Obama will be the first US president to attend India's Republic Day parade and will host a radio show with Mr Modi.
"I'd like to think the stars are aligned to finally realise the vision (of) India and America as true global partners," Obama said in an interview with India Today, a weekly magazine, published on Friday.
It has been a week of historic diplomacy in the Cuban capital.
Tonight, the extraordinary changes taking place between the USA and Cuba are illustrated in the words of a Cuban man who is hailed as a hero in his country after being jailed in the US for spying.
He has told ITV News that he would welcome a visit to Havana by President Barack Obama.
ITV News' Washington Correspondent Robert Moore has this report:
President Barack Obama has expressed his personal condolences and the sympathies of the American people on hearing about the death of King Abdullah of Saudi Arabia. In a statement, he said:
As our countries worked together to confront many challenges, I always valued King Abdullah’s perspective and appreciated our genuine and warm friendship.
As a leader, he was always candid and had the courage of his convictions.
One of those convictions was his steadfast and passionate belief in the importance of the US-Saudi relationship as a force for stability and security in the Middle East and beyond.
The closeness and strength of the partnership between our two countries is part of King Abdullah’s legacy.
The Republican House Speaker John Boehner was less than impressed by President Obama's State of the Union address:
All POTUS offered is more taxes, more government, & more of the same approach that has failed middle-class families. http://t.co/cumheM6Cud
President Obama's are the wrong priorities: growing Washington’s bureaucracy instead of America’s economy. http://t.co/cumheM6Cud
President Obama got the biggest laugh of the evening when he said "I have no more campaigns to run" before ad-libbing "I know because I won both of them".
President Obama has appealed to lawmakers to create a "better politics" and to see over partisanship to start "rebuilding trust".
He said that he knows Congress contains "good people ... on both sides of the aisle" and urged them to recognise their similarities:
A better politics is one where we debate without demonising each other; where we talk issues, and values, and principles, and facts, rather than “gotcha” moments, or trivial gaffes, or fake controversies that have nothing to do with people’s daily lives.
President Obama has said it is "time to finish the job" and close the Guantanamo Bay camp in Cuba.
He said: "Since I’ve been President, we’ve worked responsibly to cut the population of GTMO in half."
"I will not relent in my determination to shut it down," he added.
President Barack Obama made clear that he has not forgotten the debate over Internet privacy ignited by the recent hacking of Sony Corp. He said:
No foreign nation, no hacker, should be able to shut down our networks, steal our trade secrets, or invade the privacy of American families, especially our kids ...
I urge this Congress to finally pass the legislation we need to better meet the evolving threat of cyber-attacks, combat identity theft, and protect our children’s information.
If we don’t act, we’ll leave our nation and our economy vulnerable.