Israel, the United Arab Emirates and Qatar closed their airspace on Saturday. Airspace in southern Syria was also closed.

Planes that were en route to cities like Tel Aviv and Dubai early Saturday were diverted or returned to where they took off from.

The situation is changing quickly and airlines urged passengers to check their flight status online before heading to the airport.

Dubai’s airport operator said flights were halted indefinitely at Dubai International Airport, the world’s busiest airport for international flights, and the Dubai World Central — Al Maktoum International Airport on the Gulf city’s outskirts.

The closure is likely to have significant ripple effects not only for Dubai-based Emirates but for many other airlines that fly in and out of the city.

Emirates said separately that it was temporarily suspending operations to and from Dubai International Airport.

Qatar Airways Group has temporarily canceled flights to and from Doha because of the airspace closures.

Dutch airline KLM had already announced earlier in the week that it was suspending flights to and from Tel Aviv starting Sunday.

Airlines including Lufthansa, Air France, Transavia, Qatar Airways, and Pegasus have canceled all flights to Lebanon.

Virgin Atlantic canceled its flight from Heathrow Airport in London to Dubai and said it would avoid flying over Iraq, meaning flights to and from India, the Maldives and Riyadh could take slightly longer. The airline already was not flying over Iran. Virgin Atlantic said all flights would carry appropriate fuel in case they need to reroute on short notice.

British Airways said flights to Tel Aviv and Bahrain will be suspended until next week, and flights to Amman, Jordan, will be canceled Saturday.

United Airlines said flights en route to Tel Aviv and Dubai on Saturday morning were either diverted or returned to the U.S. The airline canceled flights between the U.S. and Tel Aviv through Monday and flights between the U.S. and Dubai through Sunday. It issued a travel waiver so passengers can change their flights at no cost.

Turkish Airlines said on X that flights to Lebanon, Syria, Iraq, Iran and Jordan will be suspended until Monday and flights to Qatar, Kuwait, Bahrain, the United Arab Emirates and Oman would be suspended on Saturday. The airline said additional cancellations may be announced.