Foreign Minister Hoshiyar Zebari said Sunday's bloodshed reinforced the need for the international community to help Iraq defend itself against bomb attacks as it emerges from years of sectarian conflict unleashed by the 2003 US invasion.

"The bloody Sunday explosions strengthen Iraq's demand to the UN and the Security Council to nominate a senior international envoy to come to Iraq and evaluate the degree of interference targeting stability in Iraq," Zebari told al-Arabiya television.

In Washington, a State Department official said the United States supports an inquiry to see if there has been any foreign involvement in the attacks.

"We would support the idea of the UN appointing a senior official to go into Iraq and look into these very serious allegations," said State Department spokesman Ian Kelly.

Overall violence in Iraq has fallen sharply in the past 18 months as widespread fighting between its once dominant Sunni Muslims and majority Shi'ite Muslims faded. But a stubborn Sunni Islamist insurgency continues to carry out regular bomb attacks.