Iraqi Prime Minister Nouri al-Maliki broadcast a joint appeal for national unity on Tuesday with bitter Sunni critics of his Shiite-led government — a move that may help him win U.S. help against rampant Islamists threatening Baghdad.

Just hours after al-Maliki's Shiite allies had angrily vowed to boycott any cooperation with the biggest Sunni party and his government had accused Sunni neighbor Saudi Arabia of backing "genocide," the premier's visibly uncomfortable televised appearance may reflect U.S. impatience with its Baghdad protege.

In a rerun of previous failed efforts at bridging sectarian and ethnic divisions, Shiite, Sunni and Kurdish leaders met behind closed doors and then stood frostily before cameras as Maliki's Shiite predecessor Ibrahim al-Jaafari read a statement denouncing "terrorist powers" and supporting Iraqi sovereignty.