Amman, Jordan - Jordan on Sunday condemned a drone attack that killed three US troops at an outpost near the Syrian border, after earlier saying the attack did not occur on its soil.

The official Petra news agency said Jordan "condemned the terrorist attack that targeted an outpost on the border with Syria, killing three US soldiers" and injuring others "from the US forces that are cooperating with Jordan in countering terrorism and securing the border."

After President Joe Biden announced the attack "on our forces stationed in northeast Jordan near the Syria border," Jordanian government spokesman Muhannad Mubaidin initially said the attack "did not happen in Jordan."

He had said it "targeted Al-Tanf base in Syria," where US forces are deployed as part of an international anti-jihadist coalition.

Mubaideen expressed condolences to the United States and said the attack "did not result in any casualties among officers of the Jordan Armed Forces."

Biden vowed that the United States would respond after the attack that he blamed on Iran-backed militants.

It is the first time American military personnel have been killed by hostile fire in the Middle East since the start of the Israel-Gaza war in October.