ANALYSIS-Fight or flee: decision time for Libya's Gaddafi
The third possibility is that Gaddafi will decide to negotiate an exit deal. That would possibly involve him and his family going into exile in a state which will not hand him over for prosecution to the International Criminal Court.
People who know him say Gaddafi -- beneath his eccentric image -- is a pragmatist who will cut a deal if that is what it takes to save the lives of his family.
But they also say this will not happen until he is convinced he can no longer win. His spokesman on Sunday denied there were any negotiations on Gaddafi's departure.
"If he is going to try to strike a deal he will leave it until the last minute," said Hartwell of IHS Janes. "He still thinks he has something to fight for."
The worst case scenario for the rebels and their Western backers is that the strategy of strangling Gaddafi's capital will not dislodge him. In this event, there will be a battle for Tripoli and the only thing certain then is that there will be huge loss of life.
"It would not be surprising if Gaddafi were to go out with all guns blazing so long as no deal is on the table and he does not have an exit strategy," said Anthony Skinner, an analyst with risk advisory firm Maplecroft.
"The colonel may booby trap Tripoli and loyalists may also put up a fight to the death." (Additional reporting by Peter Apps in London and David Brunnstrom in Brussels; ; Editing by Giles Elgood)
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