Arab League chief Ahmed Aboul Gheit expressed alarm on Wednesday at Turkey's planned military incursion against Syrian Kurdish fighters in northeastern Syria.
He warned that such an offensive would be a "blatant violation of Syria's sovereignty and threatens Syria's integrity."
In a statement, he warned the incursion threatens to inflame further conflicts in eastern and northern parts of the war-torn country and "could allow for the revival" of the ISIS extremist group.
Turkey has been preparing for an attack on the Kurdish fighters in Syria whom Ankara considers terrorists allied with a Kurdish insurgency within Turkey.
President Donald Trump said earlier this week the United States would step aside for an expected Turkish attack on the fighters, who have fought alongside Americans for years in their fight against ISIS.
Meanwhile, the US-backed Kurdish-led Syrian Democratic Forces and two Syrian activist groups said ISIS extremists have carried out an attack in the northern Syrian city of Raqqa, the extremists’ former de facto capital.
ISIS launched three suicide attacks against its positions in Raqqa, said the SDF. There was no word on casualties.
Raqqa is being Silently Slaughtered, an activist collective, reported an exchange of fire and a blast.
The Britain-based Syrian Observatory for Human Rights, a war monitoring group, said the attack involved two ISIS fighters who engaged in a shootout before blowing themselves up.