The US has admitted that mistakes led to a deadly strike on Syrian troops - an incident that highlighted the chaotic situation of a conflict involving multiple factions and forces. Yet it has claimed the strike did not constitute a war crime because the mistake was unintentional.

In September, the US acknowledged that coalition warplanes had carried out airstrikes that led to the deaths of at least 62 troops, injured a further 100 and opened the for an attack by Isis.

On Tuesday, Pentagon officials said the attack, involving aircraft from the UK, US, Denmark and Australia, had been intended to hit Isis forces. The operation was halted following intervention from Russia, which informed the US they were hitting Syrian forces.

Brig Gen Richard Coe claimed that because the mistake was not deliberate or a result of negligence, the attacks were not illegal under international law.

According to USA Today, Mr Coe said the mistake had its genesis in the fact that the forces the coalition warplanes struck, looked like Isis fighters.

Each country accused the other of violating terms of the cease-fire.

Secretary of State John Kerry said at the time that the airstrike was a mistake, but he claimed that Russia would not admit that Syrian or Russian warplanes had struck an aid convoy attempting to get to the rebel-held city of Aleppo. “We did it, a terrible accident,” Mr Kerry said. “Within moments of it happening, we acknowledged it. We didn’t put out a bunch of obfuscating facts