DUBAI — Four Arab nations led a diplomatic break with Qatar on Monday, moving swiftly to isolate the small but influential country in a feud that stunned the Middle East and divided a coalition of monarchies that the United States had hoped to rally to fight the Islamic State and counter Iran.
The feud, the most serious in decades among the Persian Gulf monarchies, has been simmering for years as Qatar has sought to project its influence across the region, including backing the Muslim Brotherhood and Islamist fighters in Libya and Syria. But the flaring tensions raised fears of another destabilizing conflict in a region already grappling with three civil wars and jihadist insurgencies on several fronts.
The diplomatic break also complicated U.S. efforts to rally Arab and Muslim leaders to form a united front against Sunni extremists and Iranian influence. That had been the principal reason for President Trump's visit to Riyadh, the Saudi capital, last month, a trip that the president and his allies had hailed as a success.
But observers in the Middle East warned that the trip also amounted to a tacit endorsement of Saudi Arabia’s frequently domineering and sharply contested leadership in the Middle East and was likely to aggravate local rivalries and disputes. Saudi Arabia is often accused of indirectly fueling militant views through its rigid Wahhabi brand of Islam.
“I do think it’s fair to say that it emboldened Saudi Arabia and the UAE to reshape the region and the immediate neighborhood in ways that they had wanted to do for a long time,” said Karen Young, a senior scholar at the Arab Gulf States Institute in Washington, which receives funding from the United Arab Emirates. “I think it’s because they saw an opening in American policy — that Trump would support them in efforts that could be perceived as counterterrorism.”
Qatar’s Foreign Ministry called the measures “unjustified” in a statement and said the decision to sever ties was a violation of the country’s sovereignty, and one “based on claims and allegations that have no basis in fact.”
The Indian Ocean nation of Maldives also joined the break with Qatar. But two other Persian Gulf states, Kuwait and Oman, which have frequently played mediating roles in Arab disputes, did not announce any measures against Qatar.
Secretary of State Rex Tillerson and Defense Secretary Jim Mattis, traveling in Australia on Monday, said the feud would not affect the U.S.-led coalition fighting Sunni extremist groups in the Middle East. The United States uses bases in several of the countries to launch air operations against the Islamic State group. The U.S. headquarters for the air war is at Al Udeid Air Base in Qatar.
“What we’re witnessing is a growing list of irritants in the region that have been there for some time, and obviously they have now bubbled up to a level that countries decided they needed to take action in an effort to have those differences addressed,” Tillerson said.
Other nations with strategic ties in the region, including Turkey and Russia, quickly urged efforts to keep the diplomatic spat from widening.
While the other Persian Gulf states have expressed anger over Qatar’s ties to Iran, with which it shares a massive natural gas field, others in the region also maintain strong economic relations with Tehran. The UAE is Iran’s biggest non-oil trading partner, and Oman conducts an open dialogue with the government there.
Far deeper is the dispute over Qatari support for political Islam, in particular the Muslim Brotherhood. In its early days, the Trump administration prepared an executive order designating the Brotherhood as a terrorist organization, only to pull back after a number of Arab leaders, including Jordan's King Abdullah II, advised against it. Egypt and Saudi Arabia have long pushed for Qatar to expel Brotherhood figures, as well as members of the Palestinian militant group Hamas, who live there.
Qatar has also drawn the ire of Arab neighbors for its sponsorship of the Al Jazeera television channel, which hosts frank discussions of politics in the region while amplifying Qatar’s pro-Islamist views. And Qatar is among several gulf countries, including Kuwait, Bahrain and Saudi Arabia, accused in recent years of looking the other way as their citizens privately sent money to Islamist militants abroad, including in Syria.
The statements by the Arab countries Monday, however, went far beyond the usual criticism of Qatar for supporting Sunni extremists, accusing it of interference in conflicts from Yemen to the Sinai Peninsula.
A battery of charges included some that appeared implausible. Saudi Arabia, for instance, accused Qatar of supporting Yemen’s Houthi rebels — even though Qatar has participated in a Saudi-led coalition fighting the Houthis, who have ties to Iran. Bahrain, a stalwart ally of Saudi Arabia, accused Qatar of financing “groups associated with Iran to subvert and spread chaos in Bahrain.”
The first signs of the intensifying feud emerged soon after Trump's visit to Saudi Arabia. In the days that followed, the Saudi government and its allies attacked Qatar for statements allegedly made by its emir that were sympathetic to Iran and militant groups such as Hezbollah and Hamas.
Qatar later said that the statements, which were posted on the state news agency’s website, were fake and that the agency’s site had been hacked. That explanation, however, did not stop the attacks on Qatar from media outlets loyal to the Saudi or Emirati government.
It remained unclear what exactly led the Arab states to move so suddenly and forcefully to isolate Qatar. Other experts suggested that the timing of the move might be related to the upcoming release of an FBI report on the alleged Qatari hacking. The Qatari government had invited the bureau to assist in an investigation of the incident.
And last month, a Washington-based think tank, the Foundation for Defense of Democracies, which has been supportive of the UAE and at the forefront of efforts to cancel the Iran nuclear deal, held a day-long meeting in which a series of speakers were sharply critical of Qatar. The keynote speaker was former defense secretary Robert M. Gates, who described Qatar as a strategic U.S. ally but expressed concern over its apparent support for groups that the United States considers terrorists.
But at the heart of the dispute is Qatar’s refusal to fall in line behind Saudi Arabia and its partners, said Mishaal Al Gergawi, the managing director of the Delma Institute, a political consultancy in the UAE. “Now that you have a post-Arab Spring reconstitution of some kind of alliance,” he said, “there is really little room for dissent on this side of the gulf.”
For Qatar, a peninsula nation that shares its only land border with Saudi Arabia, the effects of the partial blockade could be catastrophic, as airlines in the four Arab countries announced that they were halting flights and as residents flocked to supermarkets to hoard supplies.
There was also growing uncertainty among the large community of Egyptian expatriates who had fled Egypt’s dismal economy and found work in Qatar. Estimates of the number of Egyptian workers in Qatar range from 180,000 to 300,000.
Rania Dorrah, a 38-year-old Egyptian interior designer, said she and her husband were concerned that they would not be able to renew their work visas because of the crisis. Her husband, an accountant, tried to renew his visa Monday but was told to come back later, “because everything has been halted for now,” she said.
“What I fear the most now is to return to Egypt without notice, and this means returning back to nothing,” she said. “Absolutely nothing.”
CORRECTION: An earlier version of this story incorrectly referred to Iran's ties with Qatar. The two countries share a massive natural gas field, not an oil field.
Dan Lamothe in Sydney, Heba Farouk Mahfouz in Cairo, and Brian Murphy and Anne Gearan in Washington contributed to this report.