Kuwait's 91-year-old ruler Sheikh Sabah al-Ahmad Al-Sabah left for the United States Thursday to undergo medical treatment, his office said, days after he had surgery for an undisclosed illness.

Kuwait's 91-year-old ruler has been admitted to the hospital for a medical checkup, the oil-rich nation's state-run news agency reported Saturday.

Sheikh Sabah Al Ahmad Al Sabah was in "good health," the KUNA news agency said, citing a statement from the country's diwan minister.

Police in Kuwait "dispelled a riot" by stranded Egyptians unable to return home amid the coronavirus pandemic, authorities said early Monday, the first reported sign of unrest from the region's vast population of foreign workers who have lost their jobs over the crisis.

Online videos purported to show Kuwaiti police firing tear gas at the demonstrators overnight, who earlier chanted: "Where is our embassy?"

The Philippines said Friday it was reimposing a ban on its citizens going to work in Kuwait after a Filipina was allegedly killed by her employer, echoing a 2018 row between the two countries.

Kuwait's prime minister submitted his resignation Thursday along with his cabinet, officials said, amid infighting between ministers and criticism of their performance.

Prime Minister Sheikh Jaber Mubarak Al-Sabah "submitted the resignation of the cabinet to the emir... in order to allow for a cabinet reshuffle," government spokesman Tareq al-Mazrem said in a statement.

Kuwait's ruler Emir Sheikh Sabah al-Ahmad Al-Sabah returned home Wednesday after undergoing medical tests in the United States, according to the official KUNA news agency.

Kuwait's army said Wednesday it was raising its readiness levels and carrying out military exercises, amid soaring regional tensions after neighbouring Iran was accused of attacking Saudi oil infrastructure.

Kuwait is investigating accounts that a drone intruded its airspace and flew over the royal palace Saturday, the same day a devastating strike was launched on Saudi oil infrastructure.

Yemen's Huthi rebels -- who are aligned with Tehran -- claimed the attack on two oil facilities which cut Saudi production by half, but the United States has blamed Iran and there is also speculation the assault may have been launched from Iraq.

Kuwait says its ruling 90-year-old emir has left a U.S. hospital after having "successful checkups" that forced him to cancel a visit to the White House.

The state-run KUNA news agency reported early Friday that Sheikh Sabah Al Ahmad Al Sabah's checkups "showed reassuring results."

The ruler of Kuwait, Emir Sheikh Sabah al-Ahmad Al-Sabah, has been admitted to a hospital in the United States for "medical tests", a senior official said on Sunday.