Speaking at the 19th Asian Security Conference in Delhi organised by the Institute of Defence Studies and Analyses, Mr Durrani said, ''The terror attack in Mumbai, carried out by a terrorist group based in Pakistan on 26 November 2008, is a classic trans-border terrorist event. I hate to admit this, but it is true. Unfortunately, mistrust overruled common sense".
The mastermind of the attack, Lashkar-e-Taiba chief Hafiz Saeed, has "no utility for Pakistan and strong action must be taken" against him, Mr Durrani added.
Hafiz Saeed was recently put under house arrest and booked under Pakistan's Anti-Terrorism Act, which severely restricts his movement and funds. It was seen as a reaction by many to recent pressure by the new Trump Administration. Pakistan has reacted to the news saying it was rubbish. Mr Durrani was sacked earlier after he said Kasab was a Pakistani national.
Mr Durrani, who was the NSA in Pakistan when 10 Pakistani terrorists launched coordinated attacks across Mumbai in 2008 killing 166 people, maintained that ''India and Pak are more focused on blaming each other rather than extending cooperation in fighting terrorism. For example, lately, violence across the Line of Control in Kashmir has escalated''.
Also present at the conference were the current NSA of Afghanistan and Defence Minister Manohar Parrikar.
Mohammad Hanif Atmar, the National Security Advisor of Afghanistan, said, "We share the region with Pakistan, which has the highest concentration of terrorists anywhere".