The Tonga Women and Children's Crisis Centre is calling for a referendum on the decision to send troops to Afghanistan.
The call follows the government's agreement to a British request to send soldiers, in four rotations of 55, to the United Kingdom's Camp Bastion base in Helmand Province, from this November.
The UK is to pay the costs involved in the deployment, which Tonga needs to recruit more soldiers to fulfil the commitment.
The centre's director, Ofa Ki-Levuka Guttenbeil-Likiliki, says there should have been public consultation before the decision was made.
"We're questioning the process. We're questioning the rush. And we're questioning, so what, if the British Prime Minister or the government has written to us asking us for more troops. It seems like the older brother bullying the younger brother to get involved in something that really, we shouldn't be getting involved in at all."
Ofa Guttenbeil Likiliki says a petition being circulated will support the drive for a referendum.