Defending the 'lenient' sentence, US Secretary of State Hillary Clinton said Headley had yielded significant information to help India and the US prevent Mumbai-like attacks in future.
"I think it is unfinished business that we are not in any way walking away from. I'm leaving office, but I can assure you and the Indian people this remains one of our very highest priorities," Clinton said when asked if she was satisfied with the success that she had in bringing the perpetrators of 26/11 to justice during her tenure.
Clinton, 65, who is set to leave the State Department on February 1, was interacting with global audiences at a farewell talk through a satellite link.
"A lot of useful information was obtained. And I think that this sentence represents both the punishment that he (Headley) richly deserves for his participation but also a recognition of the role that he has played and is expected to continue to play in supporting Indian and American efforts to prevent the kind of horrific attack that occurred in Mumbai," she said while responding to an Indian journalist's query on bringing to justice the perpetrators of 26/11.
The sentence for Headley for his role in plotting the Mumbai attack of 2008 left India majorly disappointed.
Under the plea bargain agreement Headley reached with the US government, he could have been sentenced to a life in prison, but the prosecutors only sought a maximum of 35 years for the rogue DEA agent, leaving a slight possibility that the 52-year-old might walk out of prison.
India had pressed for extradition of Headley but that too was ruled out after the LeT operative agreed to cooperate with the US agencies.