Mr. Friedman declined to say how the United States would respond if Mr. Netanyahu moved to annex West Bank land unilaterally.

“We really don’t have a view until we understand how much, on what terms, why does it make sense, why is it good for Israel, why is it good for the region, why does it not create more problems than it solves,” Mr. Friedman said. “These are all things that we’d want to understand, and I don’t want to prejudge.”

He accused the Obama administration, in allowing passage of a United Nations resolution in 2016 that condemned Israeli settlements as a “flagrant violation” of international law, of giving credence to Palestinian arguments “that the entire West Bank and East Jerusalem belong to them.”

“Certainly Israel’s entitled to retain some portion of it,” he said of the West Bank.