Indian Prime Minister Manmohan Singh said on Tuesday that Pakistan was whipping up war hysteria, and that the Mumbai attacks must have had support from some official agencies within its nuclear-armed neighbour.
"Today, even as Pakistan engages in whipping up war hysteria, our nation remains steadfastly united and if anything the process of national consolidation is becoming stronger," Mr Singh told a security conference in the capital Delhi.
"The terrorist attack in Mumbai in November last year was carried out by a Pakistan-based outfit, the Lashkar-e-Taiba.
"There is enough evidence to show that, given the sophistication and military precision of the attack, it must have had the support of some official agencies in Pakistan."
The co-ordinated attacks in Mumbai by 10 gunmen killed 179 people, and have revived hostilities between the two countries, which have fought three wars since independence from Britain in 1947.
On Monday, India handed over evidence to Pakistan that it said linked Pakistani militants to the Mumbai attacks, including data from satellite phones and the confession of a surviving attacker.
Pakistan denies any involvement.