"It was also a signal to other regional players to show what kind of 'mistakes' the US could do," he added.
"Taking into account my work in Iraq and analysis of the recent developments in Syria, I can say that the airstrike is unlikely to have been done by a mistake," Selcen said.
In fact, Russia raised a question on who is controlling US policy – the White House or the Pentagon.
"We know that the US military has opposed the ceasefire deal with Russia on Syria. Defense Secretary Ashton Carter said that this agreement violated the law. This looked like a mutiny within the US government. As I see, the Pentagon made an attempt to sabotage the agreement and undermine Moscow-Washington cooperation before it even started," the diplomat said.
"Look how far our power and influence can reach. Each of you should think twice before acting recklessly against us or we could respond with such 'mistakes,'" Selcen said.
On Saturday, aircraft of the anti-Daesh coalition carried out four airstrikes against positions of the Syrian Army near Deir ez-Zor, leaving 62 personnel dead and some 100 wounded. The Pentagon said the airstrike was a mistake, with the intended target being Daesh forces in the area.