The Fiji Opposition Labour Party says about 10,000 eligible voters can not vote in next month's general election because of bureaucratic bungling.
Voting is compulsory under Fiji law, but the voters are unregistered and unable to participate.
The Labour party says the Supervisor of Elections, Semesa Karavaki, and the Electoral Commission, are to blame.
A spokesman for the party, Lekh Ram Vayeshnoi, says the registration process was mishandled.
"It is a huge discrepancy and a failure on the part of the authorities concerned and here it is the Supervisor of Elections and the Electoral Commission. They should take the full blame of the discrepancy."
The party is due to announce the details of fresh legal proceedings against the Elections Office after the Suva High Court struck out its application seeking to delay the election.
Mr Karavaki says the registration rate is high, with 95 percent of the estimated 475,000 eligible voters registering.
He says it's unfortunate that so many eligible voters have not bothered to register.