Addressing a gathering, Shankar described the relations between New Delhi and Washington as attaining "unprecedented progress."
The envoy said the civil nuclear agreement is a "symbol of and instrument for the transformation in our relationship."
Shankar noted that the deal would "boost bilateral economic ties and also address our shared concerns on energy security and climate change."
She further said that India would increase nuclear energy generation from 4,000 MW at present to 20,000 MW by 2020.
"India is today the most competitive producer of small nuclear power plants," she said.
"As worldwide interest in nuclear energy revives, including in the US, India looks forward to building productive international partnerships in this field," she added.