Britain is to step up the campaign against Muammar Gaddafi by sending in attack helicopters amid claims that the Libyan dictator is increasingly paranoid and "on the run".
MI6 has told David Cameron it has discovered that Gaddafi's behaviour is becoming even more erratic as Nato strikes take their toll.
He is said to be moving between hospitals in the Tripoli area nightly in an apparent bid to evade missiles - such as the ones which killed one of his sons last month. Gaddafi has now not been seen in public since May 11, and his commanders have apparently stopped using telephones for fear of being overheard.
An inability to communicate is hampering their ability to fight, according to a senior UK diplomatic source, and there is also evidence of further defections from the military.
"There is a picture building up of a man who is paranoid and a regime that is feeling the pressure and beginning to fracture," the source said. "He is on the run."
The intelligence is understood to have persuaded the Prime Minister that the time is right to "turn the screw".
Mr Cameron, Defence Secretary Liam Fox and military chiefs have agreed to put four Apache attack helicopters at the disposal of the Nato operation, alongside existing warplane deployments.
The deadly aircraft can carry out strikes at closer quarters, reducing the potential for collateral damage and allowing a wider range of targets to be taken on. They are expected to be used against Gaddafi's troops in built-up areas of Misrata. The Apaches could begin operating from HMS Ocean, which is in the Mediterranean, almost immediately.
On Thursday, Mr Cameron and French president Nicolas Sarkozy discussed the situation at the G8 summit in France, with both leaders agreeing that the pressure on Gaddafi must be increased. Mr Sarkozy has already authorised the use of 12 French attack helicopters, flying from the amphibious assault ship Le Tonnerre.
As the conflict continued, at least five explosions were heard in Tripoli from Nato air strikes. The targets were not not immediately identified, but smoke was seen rising from the area of Gaddafi's compound.