BAGHDAD - Iraq renewed calls on Monday for a U.N. inquiry into the support given by foreign countries to insurgents after twin suicide blasts against government buildings in Baghdad killed more than 150 people.

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 U.S. invasion.

The bloody Sunday explosions strengthen Iraq's demand to the U.N. 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.

I believe this will be achieved soon, especially after (Sunday's) explosions confirmed that this issue is vital and important. We need the help of the international community.

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 U.N. appointing a senior official to go into Iraq and look into these very serious allegations, said State Department spokesman Ian Kelly.

What happened was so utterly horrific that the circumstances surrounding it need to be looked into, he said.

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.

Iraq has blamed Sunday's attack against the Justice Ministry and the Baghdad provincial governorate, and bombings on August 19 that devastated the Foreign and Finance Ministries, on al Qaeda and supporters of Saddam Hussein's outlawed Baath party.

The government has accused neighboring Syria of providing a safe haven for Baathists plotting attacks.

SECURITY COUNCIL SILENT ON IRAQI REQUEST

Syria has denounced the accusations as immoral and bilateral relations have soured despite attempts at mediation by Turkey.

Iraqi officials have also accused some in Saudi Arabia of financing insurgents in Iraq, and neighboring power Iran has long been accused of arming and training Shi'ite militias.

Saudi Arabia and Iran reject the accusations.

After the August 19 bombings Maliki formally asked U.N. Secretary-General Ban Ki-moon to request that the U.N. Security Council set up an independent international commission of inquiry to look into the attacks. Ban forwarded Maliki's letter to the council but no action has been taken.

Maliki's request did not specifically name Syria, or any other country, but it said the blasts rise to the level of crimes of genocide and crimes against humanity punishable under international law.
The Iraqi request is similar to one that Lebanon put to the Security Council following the 2005 assassination of former Prime Minister Rafik al-Hariri. The council launched an investigation and set up a tribunal in the Netherlands, but no one has so far been indicted and inquiries continue.

U.N. spokeswoman Michele Montas told reporters in New York on Monday that Ban has been waiting for a response from the Security Council but has heard nothing so far.

The secretary-general himself wants to wait on this until he gets some clear view on what the Security Council wants, she said.

(additional reporting by Deborah Charles in Washington)

(Writing by Michael Christie; Editing by Alison Williams and Cynthia Osterman)