India's supreme court has upheld the death sentence of the only surviving member of the group behind the 2008 Mumbai attacks that killed 166 people.

A Mumbai court had convicted 24-year-old Mohammed Ajmal Kasab of murder, waging war against India, conspiracy and terrorism in May 2010 and sentenced the Pakistani national to death.

The sentence was confirmed by the Maharashtra high court in February last year.

The judges also rejected his claim that he had been denied a fair trial.

"In view of the nature of the gravity of his crime and the fact that he participated in waging war against the country, we have no option but to uphold his death penalty," Supreme Court Justices Aftab Alam and CK Prasad ruled on Wednesday morning.

It was not immediately clear what Kasab's next step would be, but legally he can still appeal to India's president for mercy.

Gopal Subramaniam, prosecutor, hailed the verdict as "a complete victory of the due processes of law".

"It was a case argued in a completely professional and dispassionate manner," said Subramaniam.

Kasab and nine other attackers rampaged through Mumbai for three days in November 2008, attacking two luxury hotels, a Jewish centre and a packed train station.

Kasab and an accomplice carried out the assault on the station, killing 52 people.

India blamed the Pakistan-based armed group Lashkar-e-Taiba for the attacks.

Pakistan acknowledged the assault had been partially planned in Pakistan and that Kasab was a Pakistani citizen, only after initially denying the claims.

Source: Agencies