Thousands of soldiers from 18 countries are taking part in military drills in Jordan jointly overseen by the US army, amid a US-led coalition strikes against the Islamic State of Iraq and the Levant (ISIL) group.
Around 10,000 troops are participating in the fifth "Eager Lion" annual war games, which will last for two weeks.
Since the last drill, ISIL has seized large areas of Syria and Iraq and is seen as a threat to the stability of Jordan, a Western ally.
Jordan's Brigadier General Fahad al-Damen, in charge of joint training, told reporters that the rise of extremist groups mandates cooperation "to fight all aspects and types of terrorism."
US major general Rick Mattson, meanwhile, told reporters in the Jordanian capital Amman that the military drills "have nothing to do with what is currently happening in the region."
"The more we work together the stronger we are."
Mattson said the drill will include responses to conventional and unconventional threats, including border security.
As well as troops from the US and Jordan, military contingents from several nearby Arab states and troops from France, Italy and Pakistan will take part in drills in the Jordanian desert.
The exercises will focus on challenges such as "combating terrorism" and border security, said Jordanian Brigadier General Fhad al-Damin.
Jordan has intensified its air raids against ISIL since the armed group burned alive one of its pilots who crashed in Syria earlier this year, but there are fears its participation in US-led strikes could drag the kingdom into nearby conflicts.