Ensuring that Israel maintains military superiority over its neighbors has been a principle of U.S. foreign policy for decades, but concerns are mounting in Jerusalem and Washington that President Trump’s breakthrough Middle East diplomacy is putting that principle to the test.

The U.S.-brokered normalization accord between Israel and the United Arab Emirates last month — the first such accord with an Arab state in decades — has been accompanied by a push from the UAE to buy Lockheed Martin’s state-of-the-art F-35 Lightning II fighter jets for its military.

Mr. Trump told Fox News that he “had no problem” with selling the F-35s to the UAE, especially on the heels of the Gulf nation’s historic decision to sign the Abraham Accords, normalizing diplomatic relations with Israel.

“They would like to order quite a few F-35s. It’s the greatest fighter in the world,” the president said at a White House press conference. “They’ve definitely got the money to pay for it.”

Israeli Prime Minister Benjamin Netanyahu has publicly opposed the sale, and his aides have tried to shoot down press reports that the deal was the private price for the normalization accord. Israel right now is the only military in the region with F-35s in its fleet.

Israel’s supporters in Congress are also raising fears that the sale could tip the balance of power in the region in ways that will be hard to predict — or contain.

Rep. Brian Fitzpatrick, Pennsylvania Republican, and several other lawmakers have introduced a bipartisan bill that would reiterate America’s commitment to maintaining Israel’s qualitative military edge. The measure would require the president to consult with Israel to ensure that any of their concerns are settled and report to Congress within 60 days on the impact of the sale.