JERUSALEM — Israeli and U.S. diplomats, taking a chartered airliner on a symbolic first direct flight between Tel Aviv and Abu Dhabi, arrived in the United Arab Emirates on Monday to hammer out details of a recent agreement to establish regular relations between Israel and the UAE.

The delegations, led by senior White House adviser Jared Kushner and top aides to Israeli Prime Minister Benjamin Netanyahu, planned to discuss links that would formalize the UAE as the third Arab nation to officially embrace Israel across the spheres of diplomacy, security and commerce.

The agreement in principle was brokered recently by the Trump administration, and hopes were high in all three countries that a final deal would quickly follow.

On Saturday, the UAE abolished a law boycotting Israel, opening the way for the flight as well as agreements in the commercial, financial and other sectors, with contacts already having been made between the two countries’ agricultural ministers.

“I don’t think it’s going to take very long,” said Dore Gold, a former Israeli diplomat who was involved in the years-long effort to forge closer, if semi-secret, ties between the countries. “I think both sides are highly motivated to progress into their new relationship.”

But one of the thorniest issues to be resolved had reemerged by the time the plane landed at Abu Dhabi International Airport: The potential sale of U.S. F-35 fighters to the UAE. Israel is the only country in the region to have a fleet of the jets, the most advanced in the U.S. arsenal, and leaked reports that Washington might make them available to the Persian Gulf state after the diplomatic breakthrough have caused a storm in Israeli security circles.

“Prime Minister Netanyahu and the president will discuss that at some point,” Kushner told reporters on the plane, one of several times he has confirmed the possibility that such an arms deal has become more probable.

Netanyahu has said that Israel opposes the sale as a threat to the military advantage it wields within its historically hostile neighborhood, a strategic policy explicitly supported by billions in American weaponry.

The prime minister denied media reports that an F-35 deal was part of the agreement just reached with the UAE. A senior Israeli official, speaking on the condition of anonymity to discuss sensitive issues, said Israel has made clear to Washington that its position has not changed.

“There was no understanding on this issue connecting this breakthrough in peace with the sale of the F-35. They are not part of the deal; they are not part of the understandings around the deal,” the official said. “We are opposed to a sale that could negatively affect our qualitative military edge.”

Kushner said Monday that the United States remains committed to helping Israel keep its military advantage but that Washington also has a 30-year defense relationship with the UAE.

Israel’s “qualitative military edge is something that can be respected while also advancing our military relationship with the United Arab Emirates,” Kushner said upon arriving in Abu Dhabi.

The tensions surrounding the F-35 are unlikely to derail the agreement with the UAE, said several diplomatic and security observers. Gold, a former director general of the Israeli Foreign Ministry, noted that previous arms sales to Israel’s Arab partners were able to be finessed, including early sales of F-16s to Egypt.

Nitzan Nuriel, a former director of Israel’s counterterrorism bureau, said that “from a military point of view, the Emirates with the F-35 is a big deal, but it is not something that we cannot deal with. It is not something that they will use against us.”

Other issues still to be decided by negotiators included the exchange of ambassadors, the location of embassies and the establishment of regular transportation, business and cultural connections.

In Israel, Monday’s three-hour flight of the El Al 737 charter was hailed as a harbinger of regular commercial air service between the countries. And the decision by Saudi Arabia to allow an Israeli airliner to cross its airspace for the trip not only shaved two hours off the flight but was seen by some as a subtle endorsement of the UAE’s decision to enter an open relationship with Israel.

The Palestinian leadership and several Arab states have condemned the UAE for rewarding Israel with coveted diplomatic recognition without demanding major concessions in return. Israel, as part of the UAE deal, agreed to suspend its plans to annex Jewish settlements in the West Bank. But Palestinian leaders have hewed to a long-standing stance that Arab countries not grant normal relations before Israel withdraws from the West Bank and recognizes a Palestinian state.

Other Arab states of the Persian Gulf, driven by fears of Iran and eyeing Israel’s military and economic prowess, are said to be considering following the UAE’s lead, including Bahrain and Oman. White House officials have said that they expect other announcements soon as they seek to build diplomatic momentum before the November presidential election.

Saudi Arabia, its opening of Saudi airspace on Monday notwithstanding, has said that it remains committed to the long-standing Arab Peace Initiative, which calls for Israeli concessions in advance of normalized relations.

Ruth Eglash contributed to this report.