US Defense Chief Arrives in Iraq on Surprise Visit

Carter's visit comes after a week of political turmoil that has been a setback for Prime Minister Haider al-Abadi, and the US defense chief has said it is important to support the embattled premier.

Carter will meet officials including Abadi and Defense Minister Khaled al-Obeidi to discuss increasing American military assistance to Iraq ahead of the key battle for second city Mosul.

"The fight for Mosul is critical... and it's a very large urban scenario," a senior defense official said, Reuters reported.

"We are going to need to be more aggressive," the official said.

Carter arrived in Baghdad from the United Arab Emirates, the first stop on a Perisan Gulf tour during which he will seek to shore up support for Iraq.

He has said that "the success of the campaign against (Daesh) in Iraq does depend upon political and economic progress as well," and that "it's important that we continue to support" Abadi.

The premier has sought to replace the current cabinet of party-affiliated ministers with a govement of technocrats, but has faced major opposition from powerful parties that rely on control of ministries for patronage and funds.

Abadi's cabinet efforts were overshadowed by multiple days of chaos at parliament, where lawmakers held a sit-in, brawled in the parliament hall and sought to sack the speaker.

Daesh overran large areas north and west of Baghdad in 2014, but Iraqi forces have since regained significant ground from the extremists.

Iraqi forces have begun preparatory operations in Nineveh province, of which Mosul is the capital, but the actual assault to take the city is not expected to take place for months, and possibly not until next year.

The United States has deployed some 3,900 troops to Iraq, most of them in advisory and support roles.

Carter's trip to Iraq is the latest in a series of visits by senior Weste officials in recent days.

US Secretary of State John Kerry traveled to Iraq two weeks ago to show support for the crisis-hit govement, vowing to tu up the heat on Daesh.

And French Defense Minister Jean-Yves Le Drian came to Iraq last week, saying that Mosul and Raqa, Daesh' main stronghold in Syria, "must fall" this year.