West African army chiefs meanwhile met in Bamako to plan the roll-out of the UN-mandated, 3,300-strong regional intervention force in the former French colony.
Nigeria, which is leading the regional force, said its total commitment would be 900 troops: 300 more than previously announced.
A first contingent would have been deployed by Wednesday, said Nigerian defence spokesman Colonel Mohammed Yerima. Benin, Ghana, Niger, Senegal, Burkina Faso and Togo have also pledged troops.
French Defence Minister Jean-Yves Le Drian conceded that the Malian forces around Diabaly were struggling.
But he added: “Our presence has strengthened them.”
Mr Le Drian also confirmed reports that the insurgents were still present in the central town of Konna, despite claims from Malian officers late on Saturday that they had recaptured it.
It was the fall of this town and a threat from Islamist fighters that they would move on south to the capital that prompted France to intervene last week.
The Islamists took over the vast desert territories of northern Mali last April, exploiting the power vaccuum created by a military coup the previous month.
Since France launched its air offensive, they have fled the key northern towns that had become their strongholds and where they had imposed their brutal version of Islamic law.
But analysts have warned that their withdrawal was likely a tactical move.
“The jihadists are in it for the long-haul. They are comfortable in this situation: the vast desert, a difficult terrain, a precarious security situation,” said Tunisian Islamist expert Alaya Allani.
One resident in the northern town of Gao reported that the Islamists had cut telecommunication links late Tuesday, rendering land lines and mobile phones useless.
“They accuse residents of giving information to the soldiers,” he told AFP by satellite phone.
So far the unrest has sent 144,500 refugees fleeing to neighbouring Mauritania, Niger, Burkina Faso and Algeria, the UN humanitarian agency said on Tuesday. Another 230,000 people were internally displaced, it added.
Mali conflict: French troops prepare for ground offensive – Telegraph.co.uk
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