Tunis  - A major Tunisian opposition party has announced plans to boycott the nation's October 25 national elections, claiming that the majority party is working to manipulate the outcome.

The Progressive Democratic Party (PDP) has already been blocked from competing in 17 districts after authorities ruled its applications ineligible. That would mean 80 per cent of Tunisians would not have the option of voting for the party.

"The massive annulment of the lists was a political decision," said the PDP, saying the move was designed to keep the opposition away from government institutions.

The PDP's leader, Ahmed Nejib Chebbi, 65, already withdrew his candidacy for president in August in protest against election conditions.

President Zine El Abidine Ben Ali, 73, is running for his fifth term in office. He has won past elections with returns equalling near 100 per cent of votes cast. (dpa)