Under attack from Opposition and facing reservations within Congress, Prime Minister Manmohan Singh on Wednesday made it clear that there will be no resumption of talks with Pakistan unless it tackles terror against India emanating from its soil.

Seeking to allay apprehensions over delinking terrorism from the dialogue process as contained in the Indo-Pak joint statement issued in Egypt, he told the Lok Sabha that it is impossible for any government in India to work towards full normalisation of relations with Pakistan unless it fulfills in letter and spirit its commitment not to allow its territory to be used against India for terror.

Singh made a spirited 45-minute intervention on the debate on the controversial joint statement during which the Opposition attacked him of breaking the national consensus on foreign policy.

"All the waters of Neptune cannot wash away the sins of Sharm-el Sheikh," thundered BJP's Yashwant Sinha, who initiated the debate, and called it a "shame". Several other Opposition stalwarts attacked the government on the issue.

Singh, whose speech was repeatedly cheered by the ruling benches, dismissed as "not correct" an impression that talks with Pakistan would continue irrespective of whether Islamabad takes action against terror or not.

He held his ground on the mention of Balochistan in the joint statement saying India was ready to discuss all issues including Pakistan's "misgivings" and "false allegations" on the issue as it does not want to hide anything.

"We did not dilute our positions or our resolve to defeat terrorism by talking to any country," Singh said, noting that even other major powers affected by Pakistan-based terrorism are engaging with that country.

"Unless we talk directly to Pakistan, we will have to rely on third parties to do so. That route has severe limitations as to its effectiveness," the Prime Minister said.

Making it clear that India wanted good relations with Pakistan, he said it is "in our vital interest to make sincere efforts to live in peace with Pakistan."

He, however, added that "despite the best of intentions, we cannot move forward if terrorist attacks launched from Pakistani soil continue to kill and injure our citizens, here and abroad. That is the national position."

Singh, while responding to sharp attack by BJP on the Joint Statement, noted that dealing with Pakistan is not easy.

In this regard, he referred to his "distinguished predecessor" Atal Bihari Vajpayee and said he shared his "vision" along with "frustration" in dealing with the neighbour.

While talking about the "uncertainties" involved in the Indo-Pak relations, he pointed out how Vajpayee had opted to dialogue again and again even after Kargil aggression, Kandahar hijacking and attack on Parliament.

"Shri Vajpayee was not deterred, as a statesman should not be," Singh said as he mentioned about the then Prime Minister's "bold step" of visiting Islamabad in January 2004 that "set out a vision for a cooperative relationship" between India and Pakistan.

"I share Shri Vajpayee's vision and I have also felt his frustration," the Prime Minister said in remarks aimed at blunting the Opposition attack for the UPA government's interest to engage Pakistan despite repeated terror attacks.

Emphasising with "strength and conviction that dialogue and engagement is the best way forward," he said that India would travel more than half the way on the road to peace if Pakistani leadership shows same determination to end terrorism against India as it has done against Taliban.

He said the commitments to end terrorism against India have been made by Pakistani leadership to Vajpayee as also to him and "the people of India expect these assurances to be honoured. This government recognises that as a common national consensus."

Responding to BJP leader Yashwant Sinha's poser as to what had changed from June 16, when Singh talked tough with Pakistan President Asif Ali Zardari, and July 16, when the Joint Statement was issued after Singh-Gilani talks, the Prime Minister said "in between came the dossier (on Mumbai) which showed progress." He, however, added the progress was "not adequate".

Taking the battle to the BJP camp, the assertive Prime Minister said during its entire tenure, the NDA government has never been able to get Pakistan admit what they have accepted now despite its "tall talks".

"It is for the first time that they (Pakistan) have admitted that their nationals and a terrorist organisation based in Pakistan carried out a ghastly terrorist attack in India," Singh said.

"So, I say with all respect to Shri Yashwant Sinha, that the UPA government needs no lessons from the Opposition on how to conduct foreign affairs or secure our nation against terrorist threats," he said.

While noting that Pakistan had taken certain steps in connection with prosecution of those behind the Mumbai attacks which have been detailed in a 34-page dossier, Singh said "I have to say that they do not go far enough."

He said India needs to see "evidence that action is being taken to outlaw, disarm, and shut down the terrorist groups and their front organisations that still operate on Pakistani soil and which continue to post a grave threat to our country."

India, he said, expects that the trial of those accused in the Mumbai attacks "will make quick progress and that exemplary punishment will be meted out to those who committed this horrific crime against humanity".