Jerusalem - From the windows of the grey, cube-shaped building that houses the US embassy in Tel Aviv, staff enjoy an undisturbed view out over the Mediterranean and a beach adorned in the summer with sunbeds and parasols.
Most days the only evidence of activity is outside on the pavement: A queue of Israelis snake out of a side door, clutching their documents and watched over by Israeli soldiers as they wait expectantly for a US travel visa.
The drab exterior offers no clues of the incendiary battle raging behind the scenes over whether the embassy's days are numbered. Israel, and its allies in Donald Trump's new administration, want to relocate the embassy to Jerusalem, 70km away.
The distance may be short but the move risks a political and diplomatic earthquake, according to most analysts.
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If the Trump's White House approves the relocation, it would overturn decades of international consensus on Jerusalem.
The message to the Palestinians and Arab world would be clear and provocative, said Nabil Shaath, a senior Palestinian official and former Palestinian foreign minister.
"Moving the embassy is the same as recognising Jerusalem as Israel's united capital. It's a war crime," he told Al Jazeera.
"There's no way we or the Arab world could accept it. It would mean the end of the US as the broker of the peace process. We would fight back and mobilise the rest of the world against the move."
The Israeli army has been advising the government of Benjamin Netanyahu on the possible fallout too, according to a report last week in the Israeli daily Yedioth Ahronoth. A change of address would be seen as a US green light for Israel to extend its sovereignty over the city and its holy places, including the al-Aqsa mosque, in the view of Israeli military intelligence.
Reactions could include mass protests from the Islamic movements inside Israel; riots in the occupied Palestinian territories and neighbouring states such as Jordan, which is the official guardian of al-Aqsa; and the collapse of Mahmoud Abbas' Palestinian Authority.
The Israeli army believes the move also risks inflaming the wider Muslim world and increasing the threat of terror attacks against Israeli and Jewish sites around the world.
Moving the embassy is the same as recognising Jerusalem as Israel's united capital. It's a war crime.
Tensions over Jerusalem have been high since the United Nations announced a partition plan in late 1947. It treated the city as an internationally protected zone, separate from the Jewish and Arab states it proposed in the rest of historic Palestine.
But months later, in a war that created Israel on the Palestinian homeland, Jerusalem was divided in two, under separate Israeli and Jordanian control.
In that period, Israel worked strenuously to pressure countries to set up embassies in West Jerusalem over stiff opposition from the US, said Nimrod Goren, the author of a book in Hebrew on the battles over the US embassy's location.
"Initially, Washington stuck by the international consensus so strictly that its diplomats refused even to travel to Jerusalem for political meetings and ceremonies," Goren, who heads Mitvim, a think-tank on Israeli foreign policy, told Al Jazeera.
But US resolve weakened through the 1950s as Israel's main institutions, from the parliament to the president's office, relocated to West Jerusalem.
A further turning point came in the early 1960s. "The US started to cultivate much closer ties with Israel, especially in defence matters," he said. Washington turned a blind eye as Israel offered aid to poor, newly independent states in Africa and others in Latin America in return for establishing their embassies in Jerusalem.
By the time Israel invaded and occupied East Jerusalem in 1967, Goren observed, more than a third of the 54 diplomatic missions in Israel were located in the city.
When Israel formally annexed East Jerusalem in 1980, in violation of international law, declaring the entire city its "eternal, united capital", the US again pressured states to move out of West Jerusalem. Only El Salvador and Costa Rica remained, until they too pulled out in 2006.
Another significant shift in Washington's attitude followed the signing of the Oslo accords in 1994. Israel’s lobbyists worked hard to erode the significance of the accords, which, it was widely assumed, would entail the creation of a Palestinian state with its capital in East Jerusalem.
In 1995, the US Congress passed the Jerusalem Embassy Act , which recognised Jerusalem as the "capital" of Israel and required a change in the embassy's location by May 1999 at the latest.
Like Trump, Bill Clinton and George W Bush promised during their presidential campaigns to implement the Jerusalem Embassy Act. Yet, once in office, they baulked at the daunting ramifications.
The US president, as the chief broker in the Oslo process , could not afford to be seen pre-judging the outcome of negotiations on Jerusalem, the most contentious of the final-status issues.
The continuing sensitivity was evident during Barack Obama's presidency.
He turned to the US Supreme Court in 2015 to strike down another Congressional measure designed to confer implicit US recognition of Jerusalem as Israel's capital. The legislation would have entitled American parents of children born in Jerusalem to list "Israel" as the birthplace on their passports.
Last October, the White House also made a point of publicly correcting the dateline on a press release concerning an eulogy delivered by Obama at Shimon Peres' funeral in Jerusalem. The press release was re-issued with the word "Israel" struck through.
Will Trump take a different tack, or will he too relent on his embassy pledge now he is in office?
In an interview late on Thursday, Trump indicated that he was not in a hurry to approve the move. "I don't want to talk about it yet. It's too early," he told Fox News.
The confusing signals from his officials since his inauguration more than a week ago have hinted at a clash behind the scenes, said Nathan Thrall, a Jerusalem-based analyst with the International Crisis Group, a conflict resolution think-tank.
"The truth is no one really knows what Trump will do, even veteran US diplomats," he told Al Jazeera.
On the one hand, Trump and his closest advisers on the Middle East have gone out of their way to raise expectations. Trump has invested more political capital on the move taking place than his predecessors.
The difference in approach was underscored by his choice of ambassador to Israel. David Friedman, a former bankruptcy lawyer, is more an ideological partisan - an ally of the settlers - than a diplomat, noted Yossi Alpher, who served as an adviser to former Israeli prime minister Ehud Barak.
At the same time, however, Trump is certain to face strong institutional resistance from the US state department, said Thrall. Its officials have long opposed moving the embassy, fearing the consequences for US relations with the Arab world.
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Last month, citing national security considerations, Obama signed a presidential waiver included in the Jerusalem Embassy Act to postpone for another six months the law's implementation - as has happened without fail since it passed 22 years ago.
Trump could use Obama's waiver to save face by delaying a decision until at least June, observed Goren.
It is possible too that, despite Israeli celebrations over Trump's promise on the embassy, Netanyahu may prefer in the end to let the matter lie for a while.
"There seems to be an ambivalence among Netanyahu's circle," said Thrall. "On the one hand, he has a lot of problems on his plate at the moment [with a series of corruption investigations ] and doesn't need the possibility of triggering a conflagration in the region. And on the other, there's no great gain for him. If the US moves the embassy, European states will not follow."
That is how Palestinian officials and diplomats in Jerusalem appear to be reading recent comments from the adminstration. Shaath said: "We have signs that the administration has retreated a little. But it may simply be a delay. We can't be sure."
A European diplomat based in Israel, speaking to Al Jazeera on condition of anonymity, said: "It looks like Trump's bark may have been worse than his bite. But there's still a danger that [US ambassador] Friedman and Netanyahu will find a work-around."
Morton Klein, the head of the Zionist Organisation of American, one of Israel's key Israel lobby groups in Washington, told the Haaretz daily last week that Friedman had told him he would work out of US offices in Jerusalem.
Alpher suggested a possible scenario might be for Friedman to take over a section of the US consulate in Jerusalem, which serves the occupied territories. The US embassy could then function separately in Tel Aviv.
"If American Jewish leaders are insistent that the embassy moves, I could see the [Trump] administration choosing that as a compromise," he said.
Shaath said such a manoeuvre should fool no one. "We would not accept any sort of so-called compromise along those lines. If the ambassador is working from Jerusalem, then the embassy has moved - and we will fight it."
Source: Al Jazeera