The United States said Sunday it is ordering some embassy staff to leave Saudi Arabia as Iran launched strikes on the kingdom in retaliation for attacks by Washington and Israel.

The State Department said in a travel advisory it had “ordered non-emergency US government employees and US government employee family members to leave Saudi Arabia due to safety risks.”

The order reflects continuing concerns over possible Iranian strikes, as President Donald Trump warned that the conflict could last for weeks, while Tehran said it is prepared to respond.

The United States had previously allowed non-essential personnel to depart voluntarily but had not required them to do so.

The State Department also reiterated its warning for Americans to “reconsider travel” to Saudi Arabia, although it stopped short of advising against all travel to the kingdom, which has actively courted US businesses and political leaders.

Drones struck the US Embassy in Riyadh last week, while similar attacks caused damage at US embassies in Kuwait and the United Arab Emirates.

On Sunday, Saudi Arabia said two people were killed and 12 wounded when a projectile landed in Al Kharj province.

Iran has vowed retaliation after the United States and Israel launched a massive attack on28 February that killed the country’s supreme leader, Ayatollah Ali Khamenei.

Gulf Arab kingdoms remain closely allied with the United States, with Bahrain and Qatar hosting key US military bases.

Iranian President Masoud Pezeshkian on Saturday apologized to neighboring countries for the attacks but later warned that Iran would be “forced to respond” if their territories were used to launch strikes against Iran.