South-east Asian countries yesterday criticised United States President Donald Trump's controversial decision to recognise Jerusalem as the capital of Israel.
World leaders said the move could provoke a serious backlash, even as clashes broke out in the Palestinian territories.
As the US reversed its decades-old policy, Singapore warned against unilaterally changing Jerusalem's status, saying it would hamper the peace process.
Indonesia condemned the recognition, while Malaysian Prime Minister Najib Razak said at Umno's annual gathering: "I call on all Muslims across the world to let your voices be heard, make it clear that we strongly oppose any recognition of Jerusalem as Israel's capital for all time."
His comments in Kuala Lumpur followed a statement by Malaysia's Foreign Ministry warning that Mr Trump's move could have grave repercussions for the region's security and stability, making efforts to combat terrorism all the more difficult.
Malaysian Deputy Prime Minister Ahmad Zahid Hamidi said: "There will not only be protests, but (also) my worry is that extremist groups will take unpredictable action."
Condemning the move as well was Indonesian President Joko Widodo, who urged the US to reconsider its decision. "Such a unilateral recognition violates various resolutions of the (United Nations) Security Council and the UN General Assembly," he said in Bogor.
Indonesian Foreign Minister Retno Marsudi echoed the fierce condemnation of Mr Trump's decision by Middle Eastern countries.
"We condemn this recognition," Ms Retno, who wore the iconic black-and-white chequered Palestinian scarf, said in a speech at the Bali Democracy Forum. "Indonesia will always stand with Palestine."
A spokesman for Singapore's Ministry of Foreign Affairs (MFA) said that the future status of Jerusalem should be decided through direct negotiations between the Israelis and the Palestinians.
"The status of Jerusalem is a sensitive and complex issue with a long history. Any premature and unilateral action to alter the status of Jerusalem will impede progress for a peaceful resolution of the Middle East and Palestinian problem," the spokesman said.
"Singapore reaffirms its longstanding and consistent support for a two-state solution, which will involve the establishment of an independent Palestinian state living side-by-side in peace and security with the state of Israel," he added.
Many countries have also advocated a two-state solution, which envisions an independent Palestinian state with East Jerusalem as its capital alongside Israel.
Israel captured East Jerusalem in the 1967 Six-Day War and declared the entire city as its capital in 1980, in a move condemned by the international community.
In his speech yesterday morning Singapore time, Mr Trump described his decision as "a long overdue step to advance the peace process", saying the US still wanted a negotiated peace deal and "would support a two-state solution if agreed to by both sides".
But the move risks triggering a fresh spasm of violence in the Middle East, and is set to see widespread protests worldwide today. Hamas called it a "war declaration against Palestinians", and called for a new intifada, or uprising.
Malaysia's Foreign Ministry also warned that any attempts to recognise Jerusalem as Israel's capital are considered an act of aggression towards the Arab and Islamic world, and an infringement on the rights of Muslims and Christians.
It asked UN members to not recognise any changes to Israel's 1967 borders. "Recognition of Jerusalem as the capital of Israel ignores the reality on the ground... and contravenes international law," it said.
In a Facebook post sharing MFA's statement on the move, Singapore's Environment and Water Resources Minister Masagos Zulkifli hoped stakeholders will keep the peace as countries help to resolve the long-drawn, complex and sensitive issue.
"We must not add fodder to the situation that has for decades justified mindless violence by terrorists and enmity between neighbours - a dark history the human race can do without," he said.