Colonel Muammar Gaddafi has been broadcasting defiant audio messages since rebels moved in on Tripoli but a mystery remains over his whereabouts.
The AFP news agency quoted diplomatic sources earlier on Monday saying that Gaddafi was “very likely” to be still holed up in his compound in the capital.
Alternative theories are that he has already fled Libya.
A rebel spokesman in London said that Gaddafi has already left the country for Algeria, although that claim remains unproven.
The South African government denies it plans to fly the Gaddafi family out of Libya and offer them asylum.
One possibility could be that Venezuelan President Hugo Chavez offers Gaddafi a route into exile.
Chavez has been a vocal critic of the NATO campaign in Libya and enjoys a close relationship with the Libyan leader.