"Yesterday, Katyusha rockets were fired at the U.S. embassy, and this is painful and incorrect ... Who authorizes those parties to attack the embassy in Iraq?" Abdul Mahdi's office said in a statement after the weekly cabinet meeting.

"This act offends Iraq and is unacceptable regardless of their intentions," Abdul Mahdi said without naming the attackers.

Late on Monday, an Iraqi interior ministry's official told Xinhua that three Katyusha rockets landed near the U.S. embassy in the heavily fortified Green Zone in central Baghdad without causing casualties.

The heavily fortified Green Zone has been frequently targeted by insurgents' mortar and rocket attacks. The roughly 10-square-km zone is located on the west bank of the Tigris River, which bisects the Iraqi capital.

No group has so far claimed responsibility for the attack which came after growing tensions between the United States and Iran.

On Jan. 8, Iran fired ballistic missiles on military bases housing U.S. troops in Iraq's western province of Anbar and near the city of Erbil, the capital of the semi-autonomous region of Kurdistan.

The Iranian attack came after a U.S. drone attacked on Jan. 3 a convoy at Baghdad International Airport, killing Qassem Soleimani, commander of the Quds Force of Iran's Islamic Revolution Guards Corps, and Abu Mahdi al-Muhandis, deputy chief of Iraq's paramilitary Hashd Shaabi forces.