The aides, who spokes to CNN on condition of anonymity, said Arafat's deteriorating condition means his reign as chairman of the Palestine Liberation Organization has ended.
Arafat, 75, arrived in Paris for emergency medical care Friday and is believed to be suffering from an acute blood disorder, perhaps leukemia.
In light of Arafat's decline, Palestinian Prime Minister Ahmed Qurei and former Prime Minister Mahmoud Abbas have agreed that Qurei will head the Palestinian Authority and security services, while Abbas will become leader of the PLO and its Fatah organization.
As part of their agreement, Qurei would reportedly recognize Abbas as the main leader who would take over in the event that Arafat is fully incapacitated or dies.
Some Palestinian leaders, however, oppose making any formal plan while Arafat is alive, and would rather have communiques issued in his name.