Iran and the United States concluded a round of indirect talks in Doha, mediators said Thursday, as they kept up efforts to advance negotiations and lower tensions following recent exchanges of fire. In June, Washington and Tehran agreed a memorandum of understanding, brokered by Qatar and Pakistan, which included a 60-day ceasefire pausing the war that broke out with US-Israeli strikes in late February, as well as the reopening of the blockaded Strait of Hormuz.