Billionaire entrepreneur Richard Branson has vowed to fight for the next 40 days to save the life of a US death row inmate whose execution was postponed at the last minute.

On September 30, Richard Glossip came within hours of death in an Oklahoma prison before being granted a temporary stay of execution. 

Three hours before he was due to die by lethal injection on September 16 Richard Glossip was granted a temporary stay of execution by the Oklahoma Court of Appeals.