TOKYO - LAWYERS for the Japanese doomsday cult leader on death row for ordering a deadly nerve gas attack on the Tokyo subway in 1995 have requested a retrial, a court official said on Tuesday.

Shoko Asahara, 53, was arrested at a commune near Mount Fuji two months after the Aum sect released Nazi-invented sarin gas in rush-hour Tokyo subway trains, killing 12 people and injuring thousands.

'The lawyers filed a petition for a retrial on Monday,' a spokesman for the Tokyo District Court said without elaborating.

The move does not automatically delay his execution but local media noted there have been few cases of condemned inmates being hanged while seeking retrial.

A spokesman at the justice ministry's criminal affairs bureau told the wires the government was 'making decisions (on executions) cautiously, looking at the reasons for seeking retrials'.

Japan, the only major industrial nation other than the United States to use the death penalty, has stepped up the pace of executions recently. It has hanged 15 people so far this year, the highest annual total since 1975.

Asahara, whose real name is Chizuo Matsumoto, was sentenced to death in 2004 by the Tokyo District Court for the gas attack and other crimes.

His lawyers appealed, arguing they could not communicate with the nearly blind Asahara because he only mumbled nonsense, but the former acupuncturist lost his appeal in 2006.

The bearded guru was revered as a god by his Aum Supreme Truth sect, whose hardline followers are under constant surveillance.

His crimes resulted in a total of 27 deaths and several thousand injuries, with many of the victims still suffering serious physical and psychological effects. -- AFP