Iran called on Monday for militants to be "cleaned out" of Syria's Idlib province, as it prepared for talks with Syria and Russia about confronting the last major enclave held by rebels opposed to President Bashar Assad.
Syrian government forces are planning a phased offensive in Idlib and surrounding areas held by insurgents fighting Assad, who has been backed by both Russian and Iranian forces in the country's conflict.
U.S. Secretary of State Mike Pompeo has said Washington views any government assault on Idlib as an escalation of Syria's war, and the State Department warned that Washington would respond to any chemical attack by Damascus.