Iranian-backed Houthi rebels are keeping up their pressure with renewed attacks on government-controlled areas in Yemen. The renewed violence Tuesday adds to growing concerns that it could reignite the country's civil war, deepening fears over threats to strategic shipping routes. With the Strait of Hormuz effectively shut down by Iran, there has been a renewed focus on the Red Sea and Bab el-Mandeb Strait at Yemen’s southern tip, which is an alternate route for Saudi Arabia to ship its oil to open oceans. Iran's foreign minister underscored Tehran's stance that the Strait of Hormuz cannot be reopened until the United States ends its blockade of Iranian ports and meets other demands.