ACCRA — Ghana's ruling party was to meet on Thursday to decide on picking a new candidate for December's vote after the sudden death this week of president John Atta Mills, who had been set to seek re-election.

The 68-year-old Mills died on Tuesday at a hospital in the capital Accra after falling ill. The cause of death was not specified, though there have been unconfirmed reports in local media that he suffered from throat cancer.

Senior party figures were to meet later Thursday.

"We will look at the whole roadmap towards the selection of a flagbearer for the party," said party general secretary Johnson Asiedu Nketia.

"Our legal committee will advise us vis-a-vis the provisions of our constitution and we should be able to know whether we are going for a full congress or there will be other means of getting a flagbearer."

Ghana is viewed as a bastion of democracy in West Africa, and the transition since Mills' death has so far gone smoothly, with vice president John Dramani Mahama swiftly sworn in to replace him Tuesday, in line with the constitution.

Opposition figures have also pledged unity, while there have been a flood of tributes for Mills, widely lauded for his integrity despite some criticism that he lacked of energy and initiative -- possibly due to his illness.

The December election had already been expected to be a close one, and his National Democratic Congress will now have to sort out a host of questions, including who will run in Mills' place.

Many speculated that the 53-year-old Mahama would be the candidate, though the ruling party has shown divisions in recent months.

Nana Konadu Agyemang Rawlings, the wife of ex-military leader turned elected president Jerry Rawlings, had unsuccessfully challenged Mills for the party nomination last year.

Ghana, also a major exporter of cocoa and gold, in December 2010 joined the ranks of oil producing nations. Revenue has been steadily increasing from oil production, boosting the stakes of the upcoming vote.