US Secretary of Defense Ashton Carter made an unannounced visit to Baghdad on Monday for talks with Iraqi officials on the war against ISIL.

US Secretary of Defense Ashton Carter made an unannounced visit to Baghdad on Monday for talks with Iraqi officials on the war against the Takfiri group, ISIL (so-called Islamic State in Iraq and Levant).

The US is leading an international coalition that is carrying out strikes against ISIL and also providing training and other assistance to forces fighting the Takfiris in both Iraq and neighboring Syria.

Carter will meet officials including Prime Minister Haider al-Abadi and Defense Minister Khaled al-Obeidi to discuss “increasing American military assistance to Iraq ahead of the key battle for second city Mosul,” AFP news agency reported.

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

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