US President Donald Trump recognised Jerusalem as the capital of Israel on Wednesday and announced his plans to move the US embassy to the city.
Trump was warned by many in the Middle East and elsewhere of the "disastrous consequences" the move would have on regional stability - and any prospect of a long-lasting peace agreement between the Israelis and Palestinians.
No country currently has its embassy in Jerusalem and the international community, including the US, does not recognise Israel's jurisdiction over and ownership of the city.
Palestinians have long seen East Jerusalem as the capital of their future state.
Here is how leaders from around the world reacted:
"President Abbas warned of the dangerous consequences such a decision would have to the peace process and to the peace, security and stability of the region and of the world," Nabil Abu Rudeina, the Palestinian president's spokesperson, said in a statement after Trump's call.
Echoing Abbas' comments, Jordan's King Abdullah II told Trump that such a decision would have "dangerous repercussions on the stability and security of the region", according to a statement released by the palace.
The king also warned the US president of the risks of any decision that ran counter to a final settlement of the Arab-Israeli conflict based on the creation of an independent Palestinian state with its capital in East Jerusalem.
"Jerusalem is the key to achieving peace and stability in the region and the world," the statement said, adding that an embassy move would inflame Muslim and Christian feelings.
King Abdullah also called Abbas and said they had to both work together to "confront the consequences of this decision".
In a statement, Egyptian President Abdel Fattah el-Sisi also cautioned Trump against "taking measures that would undermine the chances of peace in the Middle East".
"The Egyptian president affirmed the Egyptian position on preserving the legal status of Jerusalem within the framework of international references and relevant UN resolutions," the statement said.
Following a separate phone conversation with Trump, Saudi King Salman also told the US president "that any American announcement regarding the situation of Jerusalem prior to reaching a permanent settlement will harm peace talks and increase tensions in the area".
A statement by state-run news agency SPA quoted the king as saying that the kingdom supported the Palestinian people and their historic rights and asserted that "such a dangerous step is likely to inflame the passions of Muslims around the world due to the great status of Jerusalem and the al-Aqsa mosque".
Iran's Supreme Leader Ayatollah Ali Khamenei said the US move was "because of their incompetence and failure".
The Syrian foreign ministry said: "[The move] is the culmination of the crime of usurping Palestine and displacing the Palestinian people."
Pope Francis said in his weekly address that the status quo that governs al-Aqsa Mosque compound should be respected. The state of Jordan has been the custodian of all Muslim and Christian sites in Jerusalem since 1994.
On Tuesday, Turkish President Recep Tayyip Erdogan threatened to cut diplomatic ties with Israel, following reports that the US was considering recognising Jerusalem as Israel's capital, a move that would be symbolised by relocating the embassy to Jerusalem.
"Jerusalem is a red line for Muslims," said Erdogan. "We implore the US once again: You cannot take this step."
Later in the day, Sigmar Gabriel, Germany's foreign minister, also warned that any US move to recognise Jerusalem "as the capital of Israel does not calm a conflict, rather it fuels it even more," and that such a move "would be a very dangerous development."
Gabriel said in Brussels that "it's in everyone's interest that this does not happen".
Federica Mogherini, the European Union's top diplomat, said "any action that would undermine" peace efforts to create two separate states for the Israelis and the Palestinians "must absolutely be avoided."
UN Secretary-General Antonio Guterres has "consistently warned against any unilateral action that would have the potential to undermine the two-state solution", his spokesman, Stephane Dujarric, told reporters in New York.
Speaking to Al Jazeera from Gaza, Hamas leader Ismail Haniya described Trump's decision as a "flagrant aggression".
"This decision is an uncalculated gamble that will know no limit to the Palestinian, Arab and Muslim reaction," he said.
"We call on stopping this decision fully because this will usher in the beginning of a time of terrible transformations, not just on the Palestinian level but on the region as a whole. This decision means the official announcement of the end of the peace process."
Arab League chief Ahmed Aboul-Gheit warned the United States not to take any measures that would change Jerusalem's current legal and political status.
Aboul-Gheit spoke on Tuesday during a meeting in Cairo of Arab League representatives gathered to discuss Trump's recognition of Jerusalem as Israel's capital. He said the possible US decision is be a "dangerous measure that would have repercussions" across the entire Mideast region.
He also urged the Trump administration to reconsider the issue.
UK Prime Minister Theresa May denounced Trump's announcement.
"We disagree with the US decision to move its embassy to Jerusalem and recognise Jerusalem as the Israeli capital before a final status agreement," May said in a statement.
"We believe it is unhelpful in terms of prospects for peace in the region. The British Embassy to Israel is based in Tel Aviv and we have no plans to move it."