Tonga's Human Rights and Democracy movement is hoping the government will look at constitutional change as a result of a conference currently being held on Tongatapu.
Chairman of the movement, Lopeti Senituli, says while Tonga is experiencing economic reform, the government should also be considering political reform.
Mr Senituli says he believes that the government will feel some pressure because three high commissioners attended an address on Tonga at the ninth Nuclear Free and Independent Pacific movement conference.
"We hope that through the presence of the three high commisssioners from New Zealand and Australia and the United Kingdom during the presentation on Tonga is sending a clear signal to the Tongan government that the governments in the neighbourhood are concerned about what is going on in Tonga."
Only nine MPs out of 30 are elected by the voting public while the others nominated from the 33 noble families.
The conference is being attended by activists and delegates from non-government organisations around the region.