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BAGHDAD, July 11 (Xinhua) -- U.S. Defense Secretary Ashton Carter met here Monday with Iraqi leaders, during which they discussed means to increase support to the Iraqi forces to recapture a strategic city from the Islamic State (IS) group.

"Prime Minister Haider al-Abadi discussed with Ashton Carter the military operations in Iraq against IS, in addition to updating security plans," said a statement released by the prime minister office.

The Iraqi Defense Ministry said in a separate statement that Defense Minister Khalid al-Obeidi also met with Carter.

"The U.S. will provide all the required support to meet the requirements of the Iraqi forces and to speed up the operations to liberate Mosul," the ministry's statement said.

Obeidi also asserted that the Iraqi preparations have reached an advanced stage for the liberation of Mosul, the capital of Iraq's northern province of Nineveh, the statement said, adding the two sides discussed the international support to liberate Nineveh province after the latest victory in Qayyara area.

During his visit, the Pentagon chief said that 560 more U.S. troops will be deployed in Iraq to help establish a newly retaken airbase of Qayyara, some 55 km south of Mosul, as a staging hub for the long-awaited battle to recapture Mosul from the IS extremist militants.

Once known as Saddam airbase, it is one of the largest airbases in the Middle East region and was widely used by the former Iraqi air force during the Iraqi-Iranian war in 1980s.

The airbase is vital for the Iraqi security forces in the coming battles that aimed to free Mosul and other areas.

Most of the new U.S. troops will be devoted to the build-up of the Qayyara airbase, including engineers, logistics personnel and other forces to help the Iraqi security forces plan to encircle and eventually retake Mosul.

Earlier in the day, Carter arrived in Baghdad on an unannounced visit.

Hundreds of U.S. marines are already deployed in Iraq, serving as trainers and advisers, and were helping the country to win the battle against the IS extremists in Iraq's western province of Anbar as well as in northern regions.

Iraq's security situation has drastically deteriorated since June 2014, when bloody clashes broke out between Iraqi security forces and IS militants.

The IS took control of the country's northern city of Mosul and later seized territories in Nineveh and other predominantly Sunni provinces.

A U.S.-led international coalition has been conducting air raids against IS targets in both Iraq and Syria.

Many blame the current chronic instability, cycle of violence, and the emergence of extremist groups such as the IS on the U.S. that invaded and occupied Iraq in March 2003.