Jihadists who have spearheaded an offensive that has overrun swathes of territory north of Baghdad pose an "existential threat" to Iraq, US Secretary of State John Kerry said on Monday.
"It is a moment of decision for Iraq's leaders," Kerry told journalists in Baghdad. "Iraq faces an existential threat and Iraq's leaders have to meet that threat."
Kerry made the remarks at the US embassy, in the heavily-fortified Green Zone, after meeting with Iraqi Prime Minister Nuri al-Maliki and other leaders from across the political and communal spectrum.
A major militant offensive, led by ISIL but involving a raft of other Sunni groups as well, began in Iraq's main northern city Mosul on June 9.
The militants took Iraq's second-biggest city the following day, swept through the surrounding province of Nineveh and took major parts of four more provinces as well.
Baghdad has appealed for US air strikes against militants, but Washington has not acceded to that request, instead offering up to 300 military advisers.