BAGHDAD, Jan. 27 -- Caretaker Iraqi Prime Minister Adel Abdul Mahdi and U.S. Secretary of State Mike Pompeo on Monday talked over the phone and condemned the rocket attack on the U.S. embassy in the Green Zone of Baghdad.

The two sides discussed strengthening the procedures of the Iraqi security forces responsible for protecting the U.S. embassy and other diplomatic missions, as well as following up investigations to bring those responsible for the attacks to justice, according to a statement issued by Abdul Mahdi's media office.

Abdul Mahdi highlighted the need to stay calm in the region, saying that all parties should respect Iraq's sovereignty, and refrain from interference in its internal affairs.

For his part, the U.S. Secretary of State stressed his country's readiness to hold serious discussions on the presence of foreign forces in Iraq and cooperation to achieve Iraqi sovereignty, according to the statement.

The phone call came a day after some Katyusha rockets hit the U.S. embassy in the heavily fortified Green Zone in central Baghdad.

Late on Sunday, Abdul Mahdi issued a statement on his official Twitter Page, in which he condemned the rocket attack.

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.

On Friday, Iraqi Shiite leader Moqtada al-Sadr called for a scheduled withdrawal of U.S. troops from Iraq through peaceful means.

The Iraqi parliament passed a resolution requiring the government to end the presence of foreign forces in Iraq on Jan. 5, two days after a U.S. drone strike on a convoy at Baghdad airport, which killed Qassem Soleimani, former 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.

Over 5,000 U.S. troops have been deployed in Iraq to support the Iraqi forces in the battles against the Islamic State militants, mainly providing training and advising to the Iraqi forces.