West Papuan independence campaigners are supporting a British parliamentary petition calling for investigations into Indonesia's alleged chemical weapon use in Papua.
Labour MP Alex Sobel last month filed a motion demanding the British government and the Organisation for the Prohibition of Chemical Weapons investigate.
Since then, 22 other MPs have added their names to the petition, which claims there is "sufficient documentary evidence" of chemical weapon use by Indonesia's military in Papua.
The motion said there was witness testimony and journalistic reporting showing Indonesia's military has used "burn-causing chemicals, potentially including white phosphorous".
Indonesia's military and government have described the claims as baseless.
The motion also noted increased Indonesian military and police activity in Papua's Nduga regency, where the security forces are pursuing members of the West Papua Liberation Army.
The Free West Papua Campaign said supporters in the UK can contact their local MP to register support for the motion.