Malian and French troops have retaken the town of Hombori, officials say, as they continue their campaign to regain control of northern Mali from rebels.
Hombori lies about 160km (100 miles) from the Islamist stronghold of Gao.
Earlier, French warplanes reportedly bombed rebel positions, fuel stores and ammunition dumps near Gao.
But there were also reports that rebels had blown up a bridge linking the east of the country with Niger, from where African troops plan to open a front.
The bridge is situated in the town of Tassiga, which lies on the quickest route from Niger to Gao, and spans a canyon.
However, Ibrahim Ag Idbaltanate, a former deputy in Mali’s parliament, said the bridge was not the only way to cross the canyon.
“You can make a detour of three to six miles (5-10km) and find another way to continue on the Niger-Gao road,” he said, quoted by AP news agency.
Forces from Niger and Chad had been expected to use the road to join the advance against the rebels.
Several African countries have pledged military aid to help the Malian government win back control of the north.
In another development, the UK defence ministry said on Friday it was deploying its Sentinel R1 spy plane to support French troops in Mali.
The hi-tech plane – which has radar equipment that can scan thousands of square miles in minutes – flew missions over Libya in 2011 as rebels fought to oust Col Gaddafi.
Islamists seized a vast area of northern Mali last year and have imposed strict Sharia, or Islamic law, on its inhabitants. France intervened militarily on 11 January to stop them advancing further south.
International build-up
Meanwhile, French TV has been carrying grainy images of air strikes which the military said was near the city of Gao.
Malian and Nigerien security sources also reported the strikes, saying two Islamist bases with fuel stocks and weapon dumps near Gao had been destroyed.
French and Malian troops also staged joint patrols for the first time, in the town of Douentza west of Gao, the AFP news agency said, quoting Malian sources.
The BBC’s Mark Doyle in Mali says a big international troop build-up is continuing ahead of a probable French-led air and ground offensive on Gao and other desert cities.
There are currently about 2,000 French troops in Mali.
An armed column of Chadian soldiers is making its way to Mali overland and more than 1,000 Nigerian soldiers are expected there too.
The UN refugee agency says more than 7,000 civilians have fled to neighbouring countries since 10 January to escape the fighting.
In another development, Egypt’s President Mohammed Morsi has unveiled a proposal for a peaceful resolution to the Mali conflict.
The five-point plan includes political negotiations, economic and development initiatives and co-ordinated relief efforts. Mr Morsi has spoken against military intervention in Mali.
Meanwhile, the US military commander in Africa said the Pentagon had made mistakes when training Malian troops in recent years.
Gen Carter Ham of United States Africa Command (Africom) said its forces had failed to teach “values, ethics and a military ethos”.
He was speaking after reports of abuses by Mali government troops taking part in the counter-offensive.