The three men were due to be hanged on September 9 at a jail in the southern state of Tamil Nadu after India's president rejected their final mercy pleas earlier this month.
But the Chennai high court said it had "stayed the execution of the capital punishment by eight weeks" after a further round of appeals from lawyers and state politicians who oppose the executions.
The hangings would be the first in India since 2004, when a former security guard was hanged for the rape and murder of a 14-year-old schoolgirl.
Murugan, Santhan and Perarivalan -- all known by one name -- belonged to the now-defeated Tamil Tigers militant group of Sri Lanka, which was accused of plotting the murder of Gandhi by a female suicide bomber two decades ago.
Gandhi rose to become India's youngest-ever prime minister after his mother, former premier Indira Gandhi -- who was herself assassinated in October 1984 -- and he ruled until losing the 1989 election.
The shredded clothes and the shoes Gand