WASHINGTON ― A Thursday phone call between President-elect Donald Trump and Egyptian President Abdel Fattah al-Sisi may have undermined the Obama administration’s final effort to speak out against Israeli settlement building in the occupied Palestinian territories.

After months of negotiations, the United Nations Security Council was scheduled to vote at 3 p.m. Thursday on a resolution sponsored by Egypt to condemn Israeli settlements. The U.S., which typically blocks resolutions that are critical of Israel, had vetoed a similar measure in 2011.

But following years of growing frustration with Israeli settlement expansion, the U.S. was expected to abstain from the vote this time, which would have likely allowed the measure to pass. After the vote, Secretary of State John Kerry was prepared to deliver remarks about the Middle East peace process, State Department spokesman John Kirby said in a briefing on Thursday.

But none of that happened.

On Thursday morning, Trump slammed the draft resolution as “extremely unfair to all Israelis” and urged the U.S. to veto it. Hours later, Egypt postponed the vote indefinitely.

Initial media reports cited anonymous Western diplomats blaming pressure from the Israelis for Egypt’s sudden reversal. By Thursday evening, however, Reuters had confirmed from a Trump transition official that Trump and Sisi spoke by phone about the Israeli-Palestinian conflict. CNN reported that the Israeli government privately asked Trump to intervene on their behalf.

From the start, the idea that Egypt would have reversed itself because of pressure from the Israelis didn’t pass muster among those who closely follow Middle East politics.

Pushback from the Israelis over the settlement measure wouldn’t have come as a surprise to the Egyptians, who had been discussing it for months, Yousef Munayyer, executive director of the U.S. Campaign for Palestinian Rights, told The Huffington Post.

In a month or so, it’s not Obama they're going to be dealing with ― it’s Trump. Yousef Munayyer, of the U.S. Campaign for Palestinian Rights, on Egypt's thinking process

“What [the Egyptians] weren’t necessarily expecting or prepared to deal with is Trump coming out against it in the way he did,” Munayyer said. “In a month or so, it’s not Obama they’re going to be dealing with ― it’s Trump.”

Although the State Department declined to comment on how the U.S. would have voted on the resolution if it hadn’t been postponed, multiple sources familiar with internal discussions told HuffPost that the U.S. was expected to abstain from voting. Doing so would have represented a significant shift in U.S. policy.

The U.S., along with most of the international community, has long viewed the Israeli settlements as illegitimate and as obstacles to peace with the Palestinians. But Washington has repeatedly opted against taking any public action beyond the occasional scolding. Choosing not to exercise its veto power in the Security Council would have signaled to the world a deep frustration with the government of Israeli Prime Minister Benjamin Netanyahu. It would have marked the Obama administration’s final pronouncement on Israeli settlements and the Israeli-Palestinian conflict more broadly.

But with a tweet, a Facebook post and a phone call to Sisi, Trump may have upended the administration’s efforts, which would have been the culmination of years of planning and internal debate.

The resolution being considered at the United Nations Security Council regarding Israel should be vetoed....cont: https://t.co/s8rXKKZNF1 — Donald J. Trump (@realDonaldTrump) December 22, 2016

There’s no guarantee that Trump’s actions ultimately caused the Egyptians to change their mind. But incoming U.S. presidents typically avoid meddling in foreign policy before they are inaugurated, so as not to send mixed messages to the international community.

“It’s unprecedented for a president-elect to tell the sitting president how to conduct foreign policy,” Munayyer said.

In the weeks before President Barack Obama took office, he stayed out of key foreign policy issues, like the agreement on the longterm presence of U.S. troops in Iraq, according to Ilan Goldenberg, who worked in the departments of Defense and State under Obama.

Kerry may still deliver a final speech about the Middle East peace process, Kirby said. But there’s no word from the Egyptian mission to the U.N. on whether a vote on the settlements resolution will be rescheduled before Obama leaves office. If there is no vote before Trump becomes president next month, there is little chance of the U.S. not blocking the measure afterward.

On the campaign trail, Trump encouraged Israel to “keep moving forward” with settlement construction. Last week, he announced he would nominate bankruptcy lawyer David Friedman, a longtime supporter of the settlements, to serve as the U.S. ambassador to Israel. Friedman has compared liberal Jews to the kapos, a term for Jews who guarded the Nazi labor camps. He is expected to be the first U.S. ambassador to make good on the promise to move the American embassy from Tel Aviv to the disputed city of Jerusalem.

It is also likely that Egypt’s president will avoid doing anything to upset Trump in the final days of Obama’s term. When Sisi and Trump met in September on the sidelines of the U.N. General Assembly, Trump praised the general-turned-president ― who had seized power in 2013 through a violent coup d’etat ― as a “fantastic guy” who “really took control” of Egypt. Sisi, in turn, said he had “no doubt” that Trump would be a strong leader.

After the 2013 coup, Obama temporarily cut off some of the vast supply of weapons that the U.S. sends to Egypt, a key partner in counterterrorism. Obama eventually folded and restored the weapons transfers. Still, Sisi appears eager for Trump to take office.

Sisi was one of the first world leaders to call Trump and congratulate him on his win in November. According to an Egyptian presidential statement, Cairo hoped that Trump’s presidency would “breathe a new spirit into Egyptian-American relations.”