With US President Barack Obama backing India's request for access to David Coleman Headley, National Security Adviser Shivshankar Menon will push for direct access to the American-Pakistani 26/11 plotter when he meets his counterpart James Jones on Monday.
In his 50-minute meeting with Prime Minister Manmohan Singh on Sunday at Blair House, the presidential guest house, Obama had said he was "fully supportive" of India's request for access to Headley.
"He (Obama) was fully supportive of our request for provision of such access," Foreign Secretary Nirupama Rao told journalists in Washington after the talks.
They are working through their legal system on the issue of access, said Rao.
Bolstered by Obama's support, Menon is expected to push harder for direct access to Headley when he meets Jones here Monday on the sidelines of the Nuclear Security Summit.
India wants to know from Headley details of the Lashkar-e-Taiba's so-called "Karachi Project" - a terror mission to target select Indian cities.
Headley, an American-Pakistani Lashkar-e-Taiba operative, confessed to his role in plotting the 26/11 carnage in a plea bargain in a Chicago court last month to avoid death penalty.
The 49-year-old Headley also admitted that he attended training camps in Pakistan operated by LeT on five separate occasions between 2002 and 2005.
The US' perceived dilly-dallying on granting access to Headley on grounds of legal procedures has become a sore issue in India with the opposition parties raking it up to embarrass the government which is seen to have forged close relations with the US.