WASHINGTON, Dec 30: Pakistan faces tremendous pressure from the United States to extradite to India Zaki Al Rahman Lakhvi, the alleged mastermind of the Mumbai terror attacks, US and diplomatic sources told Dawn.

The Americans are believed to have given Pakistan a taped conversation Mr Lakhvi allegedly had with the gunmen involved in the attacks.

Diplomatic sources in Washington said that American audio experts had checked the tape and concluded that it was genuine and that the speaker was Mr Lakhvi.

It is, however, not yet clear if the Americans recorded the conversation using their own surveillance methods or received the tape from the Indians who have blamed Mr Lakhvi right from the beginning.

On Dec 4, less than a week after the attacks, Indian officials told journalists in New Delhi they believed Lakhvi and Yusuf Muzammil had masterminded the Mumbai operation.

They identified both as top leaders of the Lashkar-e-Taiba group, which India claimed was behind this and other terrorist attacks in that country.

On Dec 8, Pakistani security officials told the media that they had arrested Lakhvi and some of his top lieutenants but they also said that all suspects would be tried in Pakistan and would not be handed over to India.

But officials in both New Delhi and Washington said that’s not enough and they would not be satisfied unless Islamabad followed up by prosecuting those arrested and taking further action against other militant groups linked to attacks on Indian soil.

Later, India urged Pakistan to hand over Lakhvi to Indian authorities along with at least two other suspects.

Until this week, US officials had not taken a clear stand on this issue but Lakhvi’s reported conversation with the gunmen appeared to have changed their minds. Diplomatic sources in Washington said that now the Americans were also urging Pakistan to hand over Lakhvi to New Delhi.

Reports in the US media noted that Lakhvi came from the same area as Mohammed Ajmal Kasab, the gunman arrested in Mumbai and identified by Indian authorities as one of the 10 terrorists who killed more than 170 people in Mumbai last month.

Officials in Islamabad, however, appeared reluctant to accept the intercepts of Lakhvi’s alleged confession provided to them by American and British intelligence agencies as authentic.

The intercepts allegedly showed Lakhvi having cellphone conversations with the gunmen holed up inside Mumbai’s Taj hotel during the 60-hour siege.

But officials in Pakistan said that Kasab’s confession and other evidences were inadmissible in court. They said that since the confessions had been obtained under severe pressure by the Indians, this could not be admissible in judicial process. They have insisted that the information provided would not stand scrutiny in any court.

There, however, appears to be a serious difference of opinion between Islamabad and the Pakistan Embassy in Washington over the issue.

While Islamabad was reluctant to accept the evidence as authentic, the embassy insisted that it’s authentic and that the Pakistani authorities now needed to take steps to satisfy the international community.