US troops 'ready to remain' in Iraq on Baghdad's invitation, Pentagon chief says during visit

Pentagon chief Lloyd Austin said in Iraq on Tuesday that US troops were "ready to remain" in the country at Baghdad's invitation in a non-combat role against the Islamic State group.

"These forces are operating in a non-combat advise, assist and enable role to support the Iraqi-led fight against terrorism," Austin said.

"This is a critical mission and we are proud to support our Iraqi partners but we must be able to operate safely and securely to continue this vital work."

The US Defense Secretary arrived in Iraq on an unannounced visit barely two weeks before the 20th anniversary of the US-led invasion that toppled Saddam Hussein.

Austin tweeted that the trip was aimed to "reaffirm the US-Iraq strategic partnership as we move toward a more secure, stable and sovereign Iraq".