Jordan condemned on Sunday the "terrorist attack" on a military advance post just inside its border with Syria that killed three U.S. military members and injured dozens.
In the first official statement on the attack, staunch U.S. ally Jordan said it was working with Washington to fight terrorism. Earlier, a government spokesperson had said the attack was on a U.S. base in Syria adjacent to the border but not on Jordanian soil.
A senior Jordanian security source told Reuters that Jordan had recently appealed for more advanced U.S. defence hardware and support because of worries Iran and its proxies could become embroiled more deeply in any wider Middle East conflagration.
Jordan has recently alerted Washington to the urgent need to bolster its defences against Iranian-backed militias building up their strength on Jordan's borders with Iraq and Syria, the official said.
There has been growing concern within the Jordanian military and security establishment that Iranian militias who now hold sway in southern Syria were exploiting the Gaza war to achieve a security breakthrough.
Iran's influence in Syria has expanded since Tehran's allies, including Lebanese group Hezbollah, helped Syrian President Bashar al-Assad quell a rebellion that erupted in 2011.
Iranian-backed militias hold sway on Syria's southern border with Jordan, and Amman blames them and Iran for running a drug smuggling business.
Some Jordanian officials say that pro-Iranian militias in both Iraq and Syria, which have been escalating attacks on U.S. bases in the area since the Israel-Hamas war, are also using the drug war to pile pressure on Jordan, a staunch U.S. ally that hosts hundreds of U.S. troops.
Jordan had also requested Patriot air defence systems from Washington as part of its growing concern about being caught in the crossfire if the war in Gaza pulls in Iran and its well-armed regional militias on the kingdom's borders.
The presence of U.S. troops in Jordan is a sensitive matter in a country where anti-U.S. sentiment runs high because of Washington's support for Israel in its war against Hamas.
Jordan's government signed a defence deal with the United States in January 2021, offering U.S. forces "unimpeded access" to several Jordanian military facilities, storage sites for pre-positioning equipment, and other installations.
Reporting by Suleiman Al-Khalidi