The United States has pledged to provide security guarantees to Washington's ally Qatar, which saw Israel carry out airstrikes against its territory in September, according to a presidential order issued by the White House.

"It is the policy of the United States to ensure the security and territorial integrity of the State of Qatar against any external attack," according to the decree signed by Donald Trump and dated Monday.

On September 9, Israel carried out an unprecedented attack in Qatar, targeting Hamas officials gathered in a residential complex in the heart of Doha, the capital of this Gulf country, a major ally of the United States in the region.

The attack prompted a rare rebuke from Donald Trump, an ally of Israel, who said he was "very unhappy."

Doha "welcomed the signing of the US presidential decree recognizing the attacks on its territory as a threat to American peace and security," the Qatari Foreign Ministry reacted on Wednesday.

The decree specifies that Washington will consider "any armed attack against the territory, sovereignty or critical infrastructure of the State of Qatar as a threat to the peace and security of the United States."

In the event of an attack, the US government will take "all legal and appropriate measures," including military action, it added.

In a call from the White House on Monday, Israeli Prime Minister Benjamin Netanyahu apologized to his Qatari counterpart.

Qatar claimed the following day that it had received security guarantees from the United States during the call and a promise from Israel that it would not attack it again.