WASHINGTON: U.S. President Barack Obama and Prime Minister Narendra Modi have developed a strong and productive relationship between them, a top American climate change official has said.

"President Obama and Prime Minister Modi have a very, strong and productive relationship, not just on climate change but broadly," Todd Stern, the U.S. Special Envoy on Climate Change said.

"It was a quite extraordinary fact that within the space of four months there were two head of the state visits, one first to the United States in September of 2014 and then Prime Minister Modi invited the President to India just four months later in January," the official said.

Thereafter the two leaders have been close communications with each other. "They met on the margins of the UNGA in New York and they met on the first day of the Paris meeting," Stern said.

According to Stern the meeting was a very warm and positive, cordial and detailed.

"In fact, they talked so long that - they were both supposed to go - and did go finally, but they were a little bit late to the announcement of this big Mission Innovation idea on R&D that both - well, the United States, India, China, many other countries ultimately were part of," the U.S. official said.

"So I think, that the call later, sort of more towards the end, was a check-in call to see how we were doing and to urge us all on together toward a successful conclusion. And I think it was done in that spirit, not in the spirit that there was some specific thing that had to be done before the agreement could get completed," Stern said.

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