By Agence France-Presse
What did he announce?
On December 6, 2017, Trump told the American public he would be keeping a key election pledge and transferring the US embassy in Israel from Tel Aviv to Jerusalem.
He had promised to be the most pro-Israel president in US history and the decision was hailed by Israeli Prime Minister Benjamin Netanyahu as a recognition of thousands of years of Jewish connection to the city.
Why is this controversial?
Jerusalem is a disputed city. Israel seized control of the predominantly Palestinian eastern sector in a 1967 war and later annexed it, in moves never accepted by the international community.
Palestinians see east Jerusalem as their capital, while Israelis see the whole city as their undivided capital.
Until Trump, foreign powers kept their Israeli embassies in the commercial capital Tel Aviv to avoid being seen to impact negotiations between the two sides on the future of Jerusalem.
Palestinians saw the Trump move as recognising Israel’s right to the whole of the city, including the eastern part.
Trump denied this, but the Palestinian leadership froze ties with his administration, while there were protests across the Palestinian territories.
What were the repercussions?
The new US embassy in Jerusalem eventually opened on May 14. Trump did not attend the ceremony, with his place taken by his daughter Ivanka and her husband Jared Kushner, a key presidential adviser.
It was overshadowed by huge protests by Palestinians in the Gaza Strip.
Gazans had launched regular border protests six weeks earlier, but the demonstrations, backed by the strip’s Islamist rulers Hamas, peaked on the day of the embassy move.
Tens of thousands approached the heavily protected Israeli border fence in often violent protests, with at least 62 Palestinians killed by Israeli fire on the day of the embassy move.
At least 235 Palestinians and two Israelis have died during violence in Gaza since March, mostly in border clashes.
Who has followed suit?
Netanyahu said after the Trump decision many other countries would follow suit, but so far that has failed to materialise.
Only Guatemala has fully followed through, while Paraguay moved its embassy in May but reversed course less than four months later following a change of government.
Leaders in Australia, Brazil, the Czech Republic and other countries have given indications they might move their embassies but so far have not followed through.
What happened since then?
Relations between the Trump administration and the Palestinian leadership have deteriorated, with the two sides still not communicating.
The US cut more than $500 million in Palestinian aid after Trump accused the leadership of ungratefulness on Twitter and criticised their refusal to engage with his long-promised peace plan.
The Palestinians say the White House is blatantly biased in favour of Israel and seeking to blackmail them into forfeiting their cause.
The United States has also closed its consulate in Jerusalem for Palestinians, merging it into the new US embassy.
Trump has said his embassy’s move had taken the future of Jerusalem, one of the thorniest issues in the conflict, “off the table”, but peace talks remain frozen.
Where to next?
Palestinian leaders feel they have at least partially weathered the storm, with few signs that major world powers will move their embassies in the coming months.
They continue to boycott the US administration but Trump’s team say they are still planning to make public an Israeli-Palestinian peace proposal.
The details are heavily guarded but Palestinians fear it could be unfairly slanted towards Israel, including rejecting any Palestinian claim to Jerusalem.
In September, Trump said it would be released within two and four months, but there are few signs it is imminent.
“Our timing, our strategy and our messaging is and will be entirely our own,” US Ambassador David Friedman said in a statement on November 26.
“We intend to release the president’s vision when the administration concludes that we have maximised its potential for acceptance, execution and implementation.”