By Manish Chand and Arun Kumar

Washington, Apr 12 (IANS): Highlighting Pakistan-origin terrorism as a threat to South Asia, India underlined Islamabad's lack of action against 26/11 terrorists when Washington pressed for reduction of tensions between the two neighbours.

"There was no will on part of Pakistan to punish those responsible for the terrorist attacks in Mumbai," India's Foreign Secretary Nirupama Rao told journalists here Sunday after 50-minute talks between Indian Prime Minister Manmohan Singh and Obama on the sidelines of the Nuclear Security Summit.

"Terrorist onslaught in our region, if it persisted, could affect our growth prospects and how this menace was tackled would determine the future of South Asia," Rao quoted Manmohan Singh telling Obama.

Manmohan Singh also exhorted Obama to jointly combat terrorism emanating from Pakistan. This was an issue on which India and the US stood on the same page, Manmohan Singh told Obama.

In his wide-ranging conversation, Manmohan Singh also highlighted India's concerns over the activities of anti-India terrorist outfits in Pakistan like Lashkar-e-Taiba and its chief ideologue Hafiz Saeed, suspected to be the mastermind of 26/11 Mumbai massacre.

Obama showed great sensitivity to India's concerns, Rao said adding, they said the US was engaged with Pakistan on these issues.

In his talks, Obama said that he favoured reductions of tensions between India and Pakistan, but Manmohan Singh made it clear that Pakistan needs to take convincing action against anti-India terrorists to make this possible.

The delegation-level talks led by Manmohan Singh and Obama were held in Blair House, the presidential guest house across the street from White House.