The President of Indonesia is being asked to immediately order the release of West Papuan Filep Karma from prison.
Mr Karma was jailed for 15 years in 2004 for raising the illegal Morning Star flag.
He is very ill and requires specialist medical treatment, which the Free Filep Karma Campaign says it not being provided by the Indonesian government.
It says Karma's detention is illegal - a view supported by the United Nations Working Group on Arbitrary Detention.
Last week, Amnesty International said he needed to travel from Abepura prison to Jakarta to receive treatment for a suspected tumour.