Seven members of militant group Lashkar-e-Taiba (LeT) are on trial in Pakistan for planning and orchestrating the violence that killed 166 people in the Indian commercial hub and sparked renewed tensions between the two old rivals.

India blames Pakistan-based LeT for the Mumbai attacks and has broken off talks with Pakistan, saying Islamabad must first act against militants operating from its soil, including the LeT, before a peace process can resume.

Pakistan Foreign Ministry spokesman Abdul Basit said a dossier would soon be sent to New Delhi through which the extradition of Pakistani Mohammad Ajmal Kasab, the gunman, and Fahim Ansari, an Indian accused of conducting reconnaissance of Mumbai landmarks before the attack, would be sought.

"In the context of an ongoing trial in Islamabad, it (extradition) is becoming our legal requirement and we are sending a dossier soon in this regard," Basit told Reuters. Another official said Pakistan hoped to get information from Kasab and Ansari, which could be used for the trial of the seven LeT members.

"We believe their statements, especially Kasab's, would be helpful," said the official, who declined to be identified.

Pakistani Interior Minister Rehman Malik has said warrants had been issued for the arrest of the pair.

Kasab is accused of being one of 10 gunmen who attacked Mumbai in November 2008 in a three-day rampage.

An Indian court concluded his trial in March and is due to announce its verdict on May 3. Kasab faces the death penalty if found guilty of waging war against India.

India has also been pressing Pakistan to prosecute LeT founder Hafiz Mohammad Saeed but Islamabad says New Delhi has not provided enough evidence against him.

Leaders of India and Pakistan may meet in Bhutan's capital this week on the sidelines of a summit of South Asian nations to discuss trade and the environment.

A meeting between the two nuclear-armed states' leaders could help keep alive the idea of engagement between two players whose battle for influence in Afghanistan has a direct bearing on Western efforts to stabilize a region with 1.8 billion people.