New claims of military errors in Afghanistan threw President Sarkozy on the defensive yesterday as his Government prepares to fight a parliamentary vote on the unpopular French involvement in allied operations there.

A row is raging over the August 18 ambush that killed ten French soldiers and wounded twenty-one, with media reporting that the patrol had been underprepared and poorly protected.

The Defence Ministry denied two of the most damaging claims yesterday: that an interpreter had betrayed the patrol to the Taleban, and that four soldiers were executed after being taken prisoner at the start of the battle.

The ministry did not comment on soldiers' reports that no reconnaissance had been carried out, even though the armoured column was moving into a mountainous area 56km (35 miles) east of Kabul in which Taleban insurgents were active.

France's only two helicopters were being used by President Karzai at the time. “Aerial reconnaissance was indispensable,” an officer told Le Canard Enchaîné, an investigative weekly. “But no one had yet understood that this was war.”

This reinforced a remark by General Michel Stollsteiner, the French commander in the area, who said that his troops had been “guilty of overconfidence” when they mounted the patrol. Afghan troops in the patrol had fled when fighting started, the newspaper added.

Le Monde newspaper reported that wounded troops believed that Nato airstrikes had missed their targets and hit French soldiers, as did shots fired by Afghan troops backing them up. But the US forces and Nato denied this.

A special session of parliament is to vote on France's continuing presence in Afghanistan on September 22. No main party is calling for a pullout and the Government is expected to win, but public opinion is strongly opposed to the country's involvement and especially the despatch this summer of 700 more troops to the combat zone.

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