"The United States and the world will simply not stand by to watch as ISIL's evil spreads," Kerry told reporters in Baghdad on Wednesday, using an alternative acronym for "Islamic State" (IS). Kerry was in the Iraqi capital to meet with the country's new leaders and pledge US support for eliminating the IS and the threat it poses.

He also predicted Wednesday that the international coalition Washington is seeking to build to defeat IS - which has overrun parts of northern Iraq and Syria - would ultimately succeed.

"We all know - I think we come to this with great confidence - that, ultimately, our global coalition will succeed in eliminating the threat from Iraq, from the region and from the world," Kerry said.

Kerry arrived in Iraq just two days after newly sworn-in Prime Minister Haider al-Abadi confirmed his top government ministers. The new cabinet marked a crucial step toward restoring stability in the country.

"We all have an interest in supporting the new government of Iraq at this particular critical junction," Kerry told reporters. "The coalition that is at the heart of our global strategy, I assure you, will continue to grow and deepen in the days ahead..."

Kerry's comments come hours before President Barack Obama is due to outline, in specific detail, what steps the US is prepared to take to defeat IS. Obama is scheduled make the address in a televised speech at 9 p.m. local time (0100 UTC).

"When the world hears from President Obama this evening, he will lay out with great specificity each component of a broad strategy of how to deal with ISIL," Kerry said of the speech.

hc/ksb (Reuters, AFP, AP)