Palestinians are seething with anger and a sense of betrayal over US President Donald Trump's decision to recognise the disputed city of Jerusalem as the capital of Israel.
Many heard the death knell for the long-moribund US-sponsored talks aimed at ending the Israeli-Palestinian conflict and establishing a Palestinian state alongside Israel. They also said more violence could erupt.
"Trump wants to help Israel take over the entire city. Some people may do nothing, but others are ready to fight for Jerusalem," said Hamad Abu Sbeih, 28, an unemployed resident of the walled Old City.
"This decision will ignite a fire in the region. Pressure leads to explosions," he said.
Jerusalem, specifically its eastern Old City, home to important shrines of Judaism, Christianity and Islam, is at the heart of the Israeli-Palestinian conflict.
Israeli captured Arab East Jerusalem from Jordan in the 1967 Middle East War then later annexed it in a move not recognised internationally. Palestinians want it to be the capital of a future independent state and resolution of its status is fundamental to any peace-making.
Mr Trump is due to announce later on Wednesday that the US recognises the city as Israel's capital and will move its embassy there from Tel Aviv, breaking with longtime policy.
"This is insane. You are speaking about something fateful. Jerusalem is the capital of the state of Palestine and neither the world nor our people will accept it," said Samir Al-Asmar, 58, a merchant from the Old City who was a child when it fell to Israel.
"It will not change what Jerusalem is. Jerusalem will remain Arab. Such a decision will sabotage things and people will not accept it."
Palestinian leaders have also warned the move could have dangerous consequences. Although winter rains dampened protests called for East Jerusalem, the occupied West Bank and Hamas-dominated Gaza Strip, few doubted fresh bloodshed now loomed.
Israeli security forces braced for possible unrest but police said the situation in Jerusalem was calm for now.
That could quickly change, given the religious passions that swirl around the Old City, where Al Aqsa Mosque, Islam's third-holiest shrine, abuts the Western Wall prayer plaza, a vestige of two ancient Jewish temples.
In the Palestinian coastal enclave of Gaza, demonstrators chanted "Death to America", "Death to Israel" and "Down with Mr Trump". They also burned posters depicting the US, British and Israeli flags.
China has expressed concern about the move, saying it could spark new hostility.
Chinese Foreign Ministry spokesman Geng Shuang told a regular news briefing that the status of Jerusalem was a complicated and sensitive issue and China was concerned the US decision "could sharpen regional conflict".
"All parties should do more for the peace and tranquillity of the region, behave cautiously, and avoid impacting the foundation for resolving the long-standing Palestine issue and initiating new hostility in the region," Geng said.
China has long maintained that Palestinians must be allowed to build an independent state, although it has traditionally played little role in Middle East conflicts or diplomacy, despite its reliance on the region for oil.
The process of moving the US embassy is expected to take three to four years, according to US officials, though Mr Trump will not set a timetable.
The international community does not recognise Israeli sovereignty over the entire city, home to sites holy to the Muslim, Jewish and Christian religions.