Obama greeted Modi with a "Kem chho, Mr Prime Minister" at the South gate of the White House as his guest of honour, who was a persona non grata in the US till the other day, arrived dressed in a striped white kurta and churidars and a dark blue Nehru jacket.
"Thank you very much, Mr. President," said Modi in English in response to Obama's greeting in his native Gujarati. Obama then escorted Modi to the Blue room for a working dinner that lasted 90 minutes.
Modi fasting for the Hindu festival of Navratri sipped only warm water as the two delegations sat down to eat after the Prime Minister asked them not to feel embarrassed over his not eating.
"There was great, very successful interaction between the President and the Prime Minister as they got to know each other," external affairs ministry spokesperson Syed Akbaruddin told reporters after the dinner.
Modi outlined his hopes and aspirations for India, his development vision as also his concerns and how the US could help out India.
They agreed to take up more substantive issues at their formal bilateral summit meeting on Tuesday.
Obama recalled commonalities in their life experiences. Both were relative outsiders. Both had great interest in technology and faced similar difficulties when they came to office. Modi spoke of the poor technological infrastructure.
"In general, there was great goodwill and a feeling that India and the US could work together for the benefit of the world," the spokesperson said.
The two leaders who are great votaries of digital diplomacy have collaborated in writing a joint editorial in a leading US that would be published Tuesday.
Joining them at the dinner were Vice President Joe Biden, Secretary of State John Kerry, National Security Advisor Susan Rice, USAID administrator Rajiv Shah, Assistant Secretary of State for South and Central Asia Nisha Desai Biswal.
Joining the dinner on the Indian side were External Affairs Minister Sushma Swaraj, Foreign Secretary Sujatha Singh, National Security Advisor Ajit Doval, Indian ambassador to the US S. Jaishankar and a few other officials dealing with the US.
Ahead of the dinner, the White House released a vision Statement for the US-India Strategic Partnership: "Chalein Saath Saath: Forward Together We Go."
"As leaders of two great democratic nations with diverse traditions and faiths, we share a vision for a partnership in which the United States and India work together, not just for the benefit of both our nations, but for the benefit of the world," it said.
The statement seemed to echo just what Modi had suggested earlier on Monday in an address at the Council of Foreign Relations in New York.
India and US should think of what they can do together for the whole world even as they agree to disagree on some issues, he said in response to a question about his comfort level with India-US strategic partnership.
Biden and Kerry, who will participate in Tuesday's summit as well will later host a lunch for Modi at the State Department with members of Congress, the private sector, and the Indian-American diaspora.