US President Donald Trump (File photo: Reuters)

Qatar on Wednesday welcomed Trump's order, describing it as a milestone in strengthening defense ties and bilateral cooperation, its foreign ministry said.

"In the event of such an attack, the United States shall take all lawful and appropriate measures — including diplomatic, economic and, if necessary, military — to defend the interests of the United States and of the State of Qatar and to restore peace and stability," the order said.

Trump's order goes beyond a 2022 order by his predecessor Joe Biden that designated Qatar as a major non-NATO ally, allowing increased military cooperation but falling short of promising to defend Qatar if attacked.