The new leader of Fiji's People's Democratic Party, Felix Anthony, says the country's electoral process is overly complicated and the upcoming poll will not be free and fair.
Mr Anthony, the former secretary general of the Fiji Trades Union Congress, was elected as leader at the party's annual general meeting on Saturday.
"There's little confidence in the process at the moment," he told Radio Australia's Pacific Beat program.
He said he believes the electoral process will be a disadvantage to minority groups living on outer islands.
"The voting procedures that have been put in place, where people would have to vote for a number, rather than a candidate, or a party, that's very complicating," he said.
"What we're likely to see is a large number of invalid votes coming through."
The elections on September 17 will be the first since the military coup led by current interim prime minister Frank Bainimarama in December 2006.
In March, Australia and New Zealand lifted travel sanctions on senior Fijian officials in place since the military takeover.
Mr Anthony has accused Australia and New Zealand of settling for any form of democracy for the sake of convenience.
"We're very disappointed with the attitude of the Australian and New Zealand governments in this case because they seem to have been falling head over heels for the fact that we're going to have elections," he said.
The PDP is set to release its party manifesto next month.
Mr Anthony said the party is committed to protecting workers' rights, and will focus on education.
"We are determined to ensure that Fiji returns to the international stage as a respectable member of the international community, respecting international norms," he said.