By Krittivas Mukherjee
NEW DELHI (Reuters) - 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 of its nuclear-armed neighbour's official agencies.
The prime minister's comments were the latest in almost daily government criticism of Pakistan, in a sign that New Delhi has become increasingly frustrated at what it sees as Islamabad's slowness at identifying and arresting the attack's planners.
India blames Pakistan militants for the coordinated strikes in November by 10 gunmen that killed 179 people and have revived tension between two nations that have fought three wars since 1947.
"The more fragile a government, the more it tends to act in an irresponsible fashion," Singh told a security conference. "Pakistan's responses to our various demarches on terrorist attacks is an example."
"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."
India sent evidence on Monday to Pakistan that it said linked Pakistani militants to the attacks, including data from satellite phones and the confession of a surviving attacker.
The evidence was also sent to countries whose citizens were victims of the attacks, such as the United States, as India tried to corner Pakistan diplomatically into bringing the perpetrators to justice.
Singh wants international pressure to persuade Islamabad to dismantle what it says are terrorist training camps on Pakistani territory and extradite 40 suspects.
"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," Singh added.
India has said it suspects that the Pakistan military spy agency ISI gave some support to the attack.
A similar attack on India's parliament in 2001 nearly sparked a war after a massive build-up of forces on their border. While New Delhi has so far focussed on diplomatic initiatives, there are signs Indian officials are becoming frustrated.
Indian Foreign Secretary Shiv Shankar Menon said on Monday that it "beggars the imagination" that no Pakistani officials knew about preparations for the attack.
Adding to the diplomatic initiatives in the region, U.S. Assistant Secretary of State Richard Boucher met President Asif Ali Zardari and other government leaders on Monday over issues that included the Mumbai attacks.
Boucher said Pakistan had done "quite a bit," detaining a "significant number" of operatives of the militant group India says was behind the attacks, and shutting down offices of a charity the United Nations says is a front for the group. But he said there had been "not much" cooperation between the two countries and urged more.
Some analysts also say India has placed too much faith in the United States and may be disappointed -- given the weight Pakistan has in the Washington's battle against militants in neighbouring Afghanistan.
When under pressure, analysts say Pakistan can always threaten to move troops from its western border with Afghanistan, where troops are waging an unpopular, costly U.S.-supported war against Taliban militants, to its western border with India. (Writing by Alistair Scrutton; Editing by Simon Denyer and David Fox)