Tonga is said to be losing vital income as it opens up its markets in preparation for accession to the World Trade Organisation.
It has just signed a deal with New Zealand, and under WTO rules its must reach agreements with other key trade partners before it can join the world body.
The development agency Oxfam says the deal with New Zealand means a loss of tariff revenue that amounts to about of tenth of the Tongan government's income.
But Tonga's Minister of Commerce and Industry, Dr Masasso Paunga, says his country has proceeded cautiously:
"We won't get into an agreement in which we think we will totally lose out from it. There are negative sides of it and there are also positive sides of this. So have to look at stringing up a balance. We cannot be positive of achieving everything - there is also some compromises."
Tonga's Minister of Commerce and Industry, Dr Masasso Paunga.
He says it is important for Tonga to be a member of the WTO so that it can be part of global trade decision making, rather than on the outside.