July 10 (Reuters) - A Qatari delegation visited Iran on Friday in what is believed to be an effort by Doha to consolidate its role as a mediator after a recent escalation in hostilities in the Gulf, Iran's semi-official Tasnim news agency reported. Tasnim said the visit followed what it described as Qatari accusations against Iran over an alleged incident in the Strait of Hormuz and subsequent U.S. attacks on Iranian military and civilian targets.