A Tonga NGO says the decision to send troops to Afghanistan could drive the kingdom down the same path as Fiji.
The Tonga Women and Children's Crisis Centre is calling for a national referendum on a request by the United Kingdom for 270 marines for its Camp Bastion base from November.
The UK is to pay the costs involved in the deployment and although that will necessitate the recruitment of more soldiers, Tonga's Prime Minister says it won't be a drain on the country.
The crisis centre's director, Ofa Guttenbeil-Likiliki, says the government's agreement to the request inclines Tonga towards increasing militarisation.
"Unfortunately if we're going to go down this track, if we're going to send our troops to Afghanistan, that's what we're going to have to be prepared for. Militarisation of our country, Getting our troops, you know, getting our women and men who are going over there prepared for something similar to Fiji and I wouldn't be surprised if we end up going down that road."