Foreign Affairs Minister Murray McCully said New Zealand would consider its response over the next few days after consulting Pacific Islands Forum nations and the Commonwealth.
It was important to “get the line right” on sanctions between sending a strong signal and hurting citizens, he told Radio New Zealand.
“There are some other things that can be done but they all involve difficult judgments about impacting on the ability of people to trade and to travel.”
New Zealand has condemned the latest upheaval in Fiji which followed a Court of Appeal ruling last Thursday that military leader Frank Bainimarama had been in power illegally since staging a 2006 coup.
In response, Fiji President Josefa Iloilo sacked the judiciary, abrogated the constitution and then reappointed Bainimarama and his cabinet for five years.
Under emergency regulations, the Fijian news media is under orders only to publish positive stories about the political situation or risk being shut down, while foreign journalists face deportation.
“We’ve effectively got a self-appointed dictator,” McCully said as he warned New Zealanders to think twice before traveling to Fiji, which is a popular South Pacific holiday destination.
“It’s now a very much less predictable place than it was,” the minister said.
“Previous coups have seen a relatively stable environment most of the time. This time we are seeing a very ugly side of the regime where they are clamping down on personal freedoms, media freedoms and there (is a) serious sense of a crackdown on the institutions and individuals who are defying the government.”
New Zealand did not impose trade sanctions on Fiji following the 2006 coup and McCully said “it’s not under consideration yet but we’ll be talking to the forum and other countries, particularly Australia and Papua New Guinea over the next 24 hours.”
Australia has already said it could not rule out trade sanctions against Fiji if it did not return to democracy.
Fiji, a member of the 16-national regional forum, has already been warned it faces suspension if democratic elections are not held this year.
However, Commodore Bainimarama and Ratu Iloilo have said there will be no elections until 2014.