Mumbai, Jan 25 (IANS) Reacting to a US court sentencing Lashkar-e-Taiba (LeT) operative David Headley to 35 years in prison, Special Public Prosecutor Ujjawal Nikam Friday said that Headley should be made an approver in the case.

Nikam, who was the public prosecutor in the Mumbai 26/11 terror attacks case, said that by turning the mastermind of the attacks into a government approver, the state might be able to identify and subsequently punish the main perpetrators of terror.

Pakistani-American David Headley, who played a key role in planning the 2008 Mumbai terror attacks, received a 35-year jail term Thursday from a Chicago court which said the LeT operative should be "under lock and key for the rest of his life".

Nikam, however, termed the sentence as "inadequate and disproportionate".

Citing the "significant cooperation" provided by Headley to the US government's efforts to combat terrorism, the US federal prosecutors had sought only 30 to 35 years in prison for him.

"Headley agreed to provide evidence about the Mumbai attack in a plea bargain in the US court. Now that it has been done, the onus is on Pakistan to book him as one of the accused of the attacks," Nikam told IANS.

"It will help if Pakistan turns him an approver and records his evidence against LeT leader Hafiz Saeed," he added.

Nikam said that since Pakistan is citing that there was no incriminating evidence against Saeed, it is important that Headley's trial be recorded since he might say something about him.

Nikam added that Ajmal Kasabm, the Pakistani terrorist convicted for the 26/11 attacks, who was hanged Nov 21 last year, had implicated Saeed in his confession.

"Since Headley has confessed to a key role in the 26/11 conspiracy, it is possible that he might have interacted with top functionaries of LeT," Nikam said.

Headley, 52, is a Washington-born son of a Pakistani diplomat and an American mother.

Under a plea deal, US prosecutors "had agreed not to seek the death penalty against him and to not extradite him to Pakistan, India or Denmark for the offences to which he pleaded guilty".

Ten Pakistani nationals launched a brutal attack on Mumbai Nov 26, 2008, through coordinated shooting and bombing attacks, killing 166 people - including 26 foreigners - and injuring around 300 others.