In this July 11, 2017 photo U.S. Secretary of State Rex Tillerson and the Qatari Minister of Foreign Affairs Sheikh Mohammed bin Abdulrahman Al Thani take part in a press conference in Doha. Tillerson arrived in Qatar to try and mediate a dispute between the energy-rich country and its Gulf neighbours. (Alexander W. Riedel/U.S. State Department via AP)

More than three months after it began, the Persian Gulf dispute that has driven a deep wedge between America's closest allies in the region appears no closer to resolution.

The Trump administration, which depends on the gulf states as its main air and sea launchpad for the fight against the Islamic State, and as a bulwark against Iran, is starting to get worried.

"We have an awful lot of equities here," a U.S. official said. "Is it acceptable that American business starts reporting to us that contracts are getting canceled because of the climate in the gulf?" Or that the air base "from which we rain down holy hell" on militants in Syria and Iraq is endangered? Or a unified Arab bulwark against Iran is fraying?

"We're all starting to feel . . . that the Qatar crisis gets in the way of things we want to do," said the official.

The initial eruption came days after President Trump proclaimed the gulf allies united during a visit to Riyadh, Saudi Arabia, in late May. Charging that Qatar was financing terrorists and trying to undermine their governments, four nations in the region — gulf monarchies Saudi Arabia, the United Arab Emirates and Bahrain, joined by Egypt — broke relations and closed their air, land and sea borders to the tiny, energy-rich peninsula at the Straits of Hormuz.

Since then, the protagonists on both sides have waged a public war of insults and accusations, much of it through shrill, ­multimillion-dollar U.S. lobbying campaigns targeting political opinion in Washington.

The largest political ad buy of the summer came from an organization called the Saudi American Public Relation Affairs Committee, SAPRAC, which spent $1.6 million on television spots on local news and Washington broadcasts of national programs, according to data provided to The Washington Post by CMAG-Kantar Media, which tracks television advertising.

"One country in the gulf region is a threat to global security," intones the narrator of the ad over doomsday music. "President Trump, Qatar cannot be trusted."

Home to a crucial air base and more than 10,000 U.S. service members, Qatar has been cited in the past by U.S. officials for lax control over terrorist financing. But officials have also noted recent progress, and few appear to believe that Qatar's sins are much worse than those of others in the region. Instead, many chalk up the conflict to what one person involved in U.S. efforts to end it called "personal animosity" among the gulf's ruling families, and differing outlooks on how best to keep themselves in power.

U.S. and foreign officials who discussed the crisis spoke on the condition of anonymity to avoid fueling an already inflamed dispute.

At the beginning, it was Trump who spread the fire, with his open support of the accusations against Qatar. While Secretary of State Rex Tillerson and Defense Secretary Jim Mattis avoided blame and called for negotiations, Trump hailed the "wisdom" of Saudi King Salman, reveled in Saudi purchases of U.S. arms, pointed a finger at Qatar's capital, Doha, and said the United States could launch its counterterrorism warplanes from somewhere else.

During the summer, Tillerson and Jared Kushner, Trump's White House adviser and son-in-law, traveled separately to the region. In August, Tillerson sent two U.S. envoys to the gulf, but no progress was reported.

It was not until early September, after months of cajoling from Tillerson and Mattis, that Trump apparently decided it was time to put an end to the spat. "What you're seeing now is the White House trying to push this, to say enough is enough, before it begins to affect military operations," an official said.

At a Sept. 7 news conference with the visiting emir of Kuwait, whose own mediation efforts have been unsuccessful, Trump said he might have to bring the parties to the White House and handle the negotiations himself.

"Very quickly, I think, we'll have something solved," he said.

In telephone talks the next day with leaders of Saudi Arabia and Qatar, Trump facilitated a call between them.

But any rapprochement was short-lived. Within hours, both governments had publicly claimed that the other had blinked first and sought the dialogue. The effort was officially suspended.

The failure of Trump's personal diplomacy has left the United States with few options. There is little reason to think that the president, who plans to meet with some leaders from the region during the U.N. General Assembly, will have much better luck in person.

Tillerson has gone out of his way to bolster Qatar, calling demands by the Saudi-led quartet unreasonable and signing a new memorandum of understanding on terrorism financing with Doha. But the administration has left itself little leverage with the other side, unless Trump is willing to sacrifice arms sales and other ­Saudi-U.S. business deals, or temper his own fulsome praise for Saudi Arabia and the UAE, the principal Saudi partner in the fight against Qatar.

The Saudis and Emiratis have diligently courted the Trump White House. Even before the May presidential visit to Riyadh, according to U.S. intelligence, they were planning a new offensive in their long-running dispute with Qatar, correctly concluding that Trump would be sympathetic.

Small Qatar has long irked its neighbors by pursuing an impertinent foreign policy that they think contradicts their interests. A list of their 13"nonnegotiable" demands includes an end to Qatari support for political Islamic movements; , including the Muslim Brotherhood; closing Al Jazeera; , the state-funded Qatari media company;reducing ties with Iran, with which Qatar shares the world's largest gas field; and ejecting political dissidents who come from quartet countries.

Qatar has said it will talk with its accusers but will not agree to anything that impinges on its sovereignty.

As U.S. policymakers wring their hands, the main beneficiaries of the dispute so far are the lobbying firms each side has hired to influence Washington, as reflected in their filings under the Justice Department's Foreign Agents Registration Act.

In August, the Podesta Group retroactively registered for work it had done since June on behalf of SAPRAC, the Saudi purchaser of the television ads, at a monthly fee of $50,000, not including production and other expenses or marked-up media buys.

That fee is relatively small compared with the multiple other firms employed by Saudi Arabia and the UAE, some recently, and some on the payroll for years with monthly or quarterly fees in the hundreds of thousands of dollars.

Qatar has been a relative latecomer to the all-out influence war, but it has gone on a hiring spree since early summer.

Rather than attacking its accusers, Qatar has focused on print and online ads emphasizing its close security ties with the United States and its own counterterrorism efforts. South Carolina-based Nelson, Mullins, Riley & Scarborough was hired at $100,000 a month in July to "build political capital" and relationships for Qatar, and to ensure "the right information is out there, and the right people know it," said Christopher T. Kushing, the firm's managing director for public strategies.

Avenue Strategies, a firm tied to Trump campaign officials, is being paid $150,000 a month for "strategic consulting services," and former attorney general John D. ­Ashcroft's law firm received a $2.5 million retainer for "evaluating,  verifying, and as necessary, strengthening [Qatar's] anti-money laundering and counterterrorism financial compliance programs," according to the filings.

As far as the administration is concerned, however, the question of who is right has faded when compared with the potential damage of the dispute itself. The message to the gulf leaders, an official said, is that the cacophony of paid voices "is ham-handed, and they're being taken to the cleaners by those guys."

"We're trying to tell them to knock it off."

Tom Hamburger and Julie Tate contributed to this report.