The Leader of the Opposition in Fiji, Ro Teimumu Kepa, says the Fiji government's stance on the Pacific Islands Forum will create unnecessary tension in the region.
She says its response to the Forum's lifting of Fiji's suspension last week is mean-spirited and unacceptable.
The Fiji government has reiterated its position that Australia and New Zealand's role in the Forum needs to be reassessed before Fiji retakes its seat.
Suva has also suggested it may return to the Pacific's key political agency if other countries like China, Japan and the United States are made members.
Ro Teimumu says the government is just trying to punish New Zealand and Australia when it should be trying to reconstruct soured relations with the two countries.
They objected strongly to the military takeover in 2006 led by Frank Bainimarama who was elected to power last month.
New Zealand's Foreign Minister Murray McCully says it's up to Fiji how it responds but the way is now open for Fiji to participate in Forum activities.