Australian Prime Minister Malcolm Turnbull says he "regrets the loss of life" after his fighter jets were involved in a botched airstrike that shattered hopes for a ceasefire in Syria.
But Mr Turnbull refused to say definitively that an Australian jet dropped the bomb, only aircraft "participated" in the operation.
Mr Turnbull told Newshub there was an investigation underway into the strike, which was aimed at Islamic State but instead killed more than 60 soldiers from the Russia-backed Syrian Army.
"We regret the loss of life - there's an investigation underway at the moment."
Asked if Australia regretted the air strike, which shattered the fragile ceasefire in Syria, Foreign Affairs minister Julie Bishop would only say: "There's an investigation underway and we're participating in the investigation."