The election to choose the successor to Gabon's former President Omar Bongo who died last month must be held by Sept. 6 at the latest, Reuters quoted the West African country's consitutional court as saying today. A poll was originally due to be held within 45 days of the appointment of an interim president on June 10, but all main political parties in the oil-exporting state argued that organising a poll in such a short space of time would have presented great logistical difficulties.