President Donald Trump signed an executive order on Monday pledging to guarantee Qatar’s “security and territorial integrity” against “external attack.” The security guarantee, similar to NATO’s Article 5 mutual defense clause, is unprecedented for the U.S. with an Arab country.

Signed just weeks after Israel’s attempted strike on Hamas leaders in Doha, the EO says the move comes “in light of the continuing threats to the State of Qatar posed by foreign aggression” and promises that the U.S. “shall regard any armed attack” on Qatari territory, sovereignty or critical infrastructure as a “threat to the peace and security of the United States.”

Qatar also recently faced an attack from Iran, when Tehran launched missiles at the U.S.’ Al Udeied Air Base during the Israel-Iran war in June.

The order was signed on Sept. 29, the day that Israeli Prime Minister Benjamin Netanyahu met with Trump in the White House and called Qatari Prime Minister Sheikh Sheikh Mohammed bin Abdulrahman al-Thani to apologize for the strike, though it was only publicized after Netanyahu’s departure. 

The order pledges that, should Qatar face any of the described threats, “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.”

The U.S. does not have a similar security guarantee with Israel. Saudi Arabia has sought one from Washington as well, primarily through normalizing relations with Israel.