US air strikes in eastern Syria have killed up to 62 Syrian troops fighting the Islamic State in Iraq and Syria (Isis), according to a statement from the US.

A spokesperson for the US administration expressed regret for the “unintentional loss of life” in the early hours of 18 September.

Since the incident, an emergency meeting of the UN Security Council has been called by Russia to discuss the crisis.

Earlier this month, the US and Russia announced a plan for peace in Syria that aimed to start with a cessation of hostilities on 12 September.

The peace plan is now dependent on warring factions within Syria committing to peace. “In Syria, plans do not implement themselves,” said US Secretary of State John Kerry. ”So today we are announcing an arrangement which… is dependent on people’s choices and has the ability to stick, providing the region and opposition both meet their obligations.”

Violence in Syria began in 2011. It is estimated that more than 400,000 people have died in the conflict.