Fiji's National Federation Party says the government's ongoing ban of a university professor and his wife, who were born in Fiji, is a mockery of democracy.
Professor Brij Lal, who is an Australian citizen, was given 24 hours to leave Fiji in November 2009 after being detained at the Queen Elizabeth Barracks for almost three hours.
He had made public comments against the military regime.
His wife, Dr Padma Lal, was banned re-entry in January 2010 and forced to leave the country.
Professor Lal was one of the authors of the 1997 constitution, which was dumped by the regime in favour of its own document granting amnesty to perpetrators of coups.
The Immigration Minister, Timoci Natuva, told Parliament last week Professor Lal's views were prejudicial to the peace, defence, public safety, public order and the security of the government of Fiji.
However, the NFP leader, Biman Prasad, says the Lals were told that the Director of Immigration had decided to lift the ban, but was overruled by a directive from the Prime Minister's Office.