Bahrain, Egypt, Saudi Arabia and the United Arab Emirates made no demands of Qatar as their decision plunged the global travel hub into chaos and ignited the biggest diplomatic crisis in the Gulf since the 1991 war against Iraq.
US officials were blindsided by Saudi Arabia's decision to sever diplomatic ties with Qatar in a coordinated move with Egypt, Bahrain and the United Arab Emirates, the current and former officials said.
But the economic fallout loomed, as Abu Dhabi's state-owned Etihad Airways, Dubai's Emirates Airline and budget carriers Flydubai and Air Arabia said they would suspend all flights to and from Doha from Tuesday morning until further notice.
Saudi Arabia, Egypt, the United Arab Emirates and Bahrain severed diplomatic relations with Qatar in a coordinated move on Monday.
An anonymous Somali official told AP news agency at least 15 Qatar Airways flights had used Somalia's airspace on Monday, many more than on a normal day.
Food security is a major issue for Qatar given the only way into the country by land is a single border with Saudi Arabia and desert states struggle to grow food.
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In the middle of the current rift with Saudi, Krdli said Qatar is also "obliged" to maintain "a middle position" with Iran because of its shared gas exploration in the Gulf. Qatar has historically played off both sides of the Saudi-Iran rivalry.
In Riyadh, Trump made an impassioned appeal to Arab and Islamic leaders to "drive out" terrorists, while singling out Iran as a key source of funding and support for militant groups.
3-Closure of UAE airspace and seaports for all Qataris in 24 hours and banning all Qatari means of transportation, coming to or leaving the UAE, from crossing, entering or leaving the UAE territories, and taking all legal measures in collaboration with friendly countries and worldwide companies with regards to Qataris using the UAE airspace and territorial waters, from and to Qatar, for national security considerations. An Omani diplomat traveled to Qatar on Monday.
Qatar is the site of the sprawling al-Udeid Air Base, home to the forward headquarters of the US military's Central Command. Maj. Qatar's sovereign wealth fund agreed past year to invest $2.7 billion in Russia's state-run Rosneft Oil Co. Comments purportedly by Qatari Emir, Sheikh Tamim bin Hamad al-Thani, criticising Saudi Arabia had appeared on Qatari state media. "Saudi Arabia and its allies will not accept any solution short of (Qatari) capitulation", political risk consultancy Eurasia Group said in a note.
The Pentagon said USA military operations are unaffected by the rift.
The offshore North Field, which provides virtually all of Qatar's gas, is shared with Iran, Saudi Arabia's hated rival.
Marcelle Wahba, a former US ambassador to the UAE and the president of the Arab Gulf States Institute in Washington think tank, said the United States had leverage but would use it discreetly. This despite Qatar's deployment of an estimated 1,000 troops to support the two-year Saudi-led campaign there.