"I reaffirmed to the prime minister my administration's commitment to fully implement the US-India civil nuclear agreement which increases American exports and creates jobs in both countries," Obama told a joint news conference.

Singh said he was confident that Obama would "operationalize the nuclear deal as early as possible."

"There are a few 'i's and 't's that have to be crossed," Singh said. "I am confident and I have the assurance that that process can be completed without much further loss of time."

Former US president George W. Bush sealed the deal that allows India access to civilian nuclear energy despite its refusal to sign the Non-Proliferation Treaty.

Some lawmakers from Obama's Democratic Party opposed the treaty in Congress, saying it sent a bad message to nations such as Iran that are feared to be seeking nuclear weapons.