The leader of New Caledonia's anti-independence Rassemblement-UMP, Pierre Frogier, has called for Saturday's march in favour of a new flag to be cancelled.
The march was long planned but Mr Frogier says it should be stopped because the matter has been politicised by another anti-independence party, the Caledonian Union.
His call comes after two pro-independence parties decided to organise a rival march at almost the same place to push for the use of the Kanak flag in addition to the French tricolore.
The Caledonia Together Party, which has pushed the single flag cause, has described plans of another march and its timing as an act of intimidation.
The issue has been central in the recent political debate, with the Congress due to meet tomorrow to elect a new government for the third time in a month.
The French high commission is considering the implication of two rival marches and may stop them to prevent public disturbances.