NEW DELHI - REMARKS by India's prime minister that Pakistani authorities 'must have had' a hand in the Mumbai siege have been dismissed by Pakistan as propaganda that could undermine efforts to bring the perpetrators to justice.

Prime Minister Manmohan Singh on Tuesday repeated India's allegations that the November attacks were carried out by the Pakistan-based militant group Lashkar-e-Taiba and made his most forceful speech yet on the possible role of Pakistani agencies in the siege.

'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 Indian leader said, while criticizing what he called Islamabad's reluctance to crack down on militants operating in their territory.

Mr Singh's comments stopped just short of accusing Islamabad of directly aiding the gunmen and seemed aimed at keeping tensions between the bitter rivals at a slow burn, but they reflected widespread belief that multiple power centers run Pakistan.

Pakistan's foreign ministry dismissed Mr Singh's comments as 'a propaganda offensive' designed 'to whip up tensions' in the region.

They 'not only ratchet up tensions, but occlude facts and destroy all prospects of serious and objective investigations into the Mumbai attacks,' the ministry said in a statement.

Pakistani President Asif Ali Zardari meanwhile called for recognition of his country's efforts to crack down on extremists.

'We expect our friends to have the same understanding, to rise above these stateless actors who are trying to create a problem in the region,' Mr Zardari told reporters on Tuesday in Afghanistan, where he was making his first official visit since being sworn in.

Mr Singh did not name any Pakistani officials, but New Delhi has accused Pakistan's military-controlled spy agency, the Inter-Services Intelligence, of being involved in attacks against India in recent years. Pakistan's civilian government is relatively new and weak, while the ISI is thought to have a high degree of independence.

One Indian analyst said Mr Singh's speech was intended for several audiences: the Indian electorate, who will be heading to the polls in the coming months and have in the past supported confrontations with Pakistan; leaders in Islamabad, who India thinks should crack down on the terror network it says operates across the border; and the international community, which New Delhi hopes will help pressure Pakistan into action.

'The idea is to make it more than an Indo-Pak issue,' said Mahesh Rangarajan, a prominent political expert in New Delhi.

But the comments were viewed in an opposite light across the border.

'It is a cost effective strategy to isolate Pakistan,' said Rasul Bakhsh Rais, a professor of political science at Lahore University of Management Sciences.

Tuesday's verbal sparring came a day after India handed Pakistan evidence that New Delhi said proved the attacks were plotted in Pakistan. The dossier included details from the interrogation of the lone surviving gunman, recovered weapons, and intercepted communications with the suspected handlers back in Pakistan.

The investigation into the attack, which left 164 dead, showed the 10 gunmen could not have been working on their own, Mr Singh said.

'We cannot choose our neighbours,' Mr Singh said before a meeting with Indian security officials. 'Some countries like Pakistan have in the past encouraged and given sanctuary to terrorists and other forces who are antagonistic to India.'

Calls for war in India have been largely muted, with even conservative opposition politicians, who endorse a hard line toward Pakistan, adopting a fairly conciliatory approach.

While Pakistan's own rhetoric has been fairly quiet in recent days, it has also moved some of its soldiers toward the Indian border and away from the Afghan border, where Islamabad is battling militants.

Predominantly Hindu India and Muslim Pakistan have fought three wars against each other since they gained independence in 1947. -- AP