Somalia's new hard-line opposition leader promised Friday to pacify his shattered country through Islamic law, warning UN peacekeepers they will face attack if they deploy and support the government. Sheik Hassan Dahir Aweys, whose Islamic regime was ousted from power in 2006 with tacit support from the United States, is gaining influence again as a deadly insurgency ruptures Somalia. Thousands have been killed in the fighting since 2007. This week, Aweys took over the Islamist opposition movement, which operates in exile in Eritrea, pushing out a more moderate cleric who signed a peace agreement with Somalia's UN-backed government last month. The UN Security Council has said it would consider deploying peacekeepers to replace African Union troops if political reconciliation and security improve. But the badly undermanned African Union force has struggled in its efforts to keep the peace, and Aweys' accession to the leadership of the opposition does not appear to promise further reconciliation. An Iraq-style Islamic insurgency, which Aweys promised after he was driven from power with the help of Ethiopian troops, has contributed to a humanitarian emergency, with millions of Somalis dependent on aid. The United States fears Somalia could become a haven for al-Qaida.