US Secretary of State John Kerry met Palestinian president Mahmud Abbas in Jordan on Thursday for talks aimed at calming a wave of violence gripping Israel and the occupied territories.
The meeting in Amman came hours after fresh clashes broke out in east Jerusalem where Israeli police fired tear gas, percussion bombs and rubber bullets to disperse Palestinian demonstrators.
Months-long unrest in annexed east Jerusalem has in recent days spread to the occupied West Bank and Arab communities across Israel, raising fears of a new Palestinian uprising.
The meeting between Abbas and Kerry, who arrived in Jordan late on Wednesday, came a day after Israel approved plans for another 200 settler homes in annexed east Jerusalem -- a move sharply criticised by Washington.
Kerry and a sombre-looking Abbas embraced and had a brief whispered exchange as they met at the Palestinian leader's hillside home in Amman where the US and Palestinian flags hung in front of a large night-time photo of Jerusalem's flashpoint Al-Aqsa mosque.
Much of the unrest in Jerusalem has been fuelled by Israeli moves to step up settlement activity in the city's eastern sector and by religious tensions at the Al-Aqsa compound, a site holy to both Muslims and Jews.
Earlier, a tense confrontation erupted in the city's Issawiya neighbourhood as about 100 residents, including schoolchildren, tried to block a main road after police closed off several neighbourhood entrances with concrete blocks.
A local activist denounced the blocks as "collective punishment" against Palestinians in Jerusalem.
The Palestinians have also been infuriated by a far-right Jewish campaign for prayer rights at the Al-Aqsa compound, although Israel insists it has no plans to change the decades-old status quo.
Israel's Public Security Minister Yitzhak Aharonovitch said the authorities were on alert for more unrest, after several attacks in recent weeks by Palestinians wielding knives or ploughing cars into pedestrians.
"I believe there will still be terror attacks and other incidents in the near future," he said.
Abbas's spokesman said the Palestinian leader was expected to tell Kerry of his growing concerns over Israel's actions, particularly in Jerusalem.
"The Palestinian position will be made crystal clear: the Israeli violations are a red line and cannot be tolerated -- especially with the tension and Israeli escalation in Al-Aqsa and Jerusalem," Nabil Abu Rudeina told AFP.
In a letter to the UN Security Council sent on Wednesday, Palestinian ambassador Riyad Mansour demanded international intervention over Al-Aqsa, warning that tensions could "spiral out of control".
Clashes at the mosque compound have drawn sharp criticism from both the Palestinians and Jordan, which has custodial rights at the shrine.
Ahead of Kerry's arrival, King Abdullah met Abbas in Amman for talks in which he expressed his "total rejection" of Israel's "repeated aggressions and provocations in Jerusalem," a palace statement said.
In a move likely to further heighten tensions around the Al-Aqsa compound, Aharonovitch said late Wednesday that he would reinstall metal detectors at the entrances along with new facial-recognition technology.
"We'll increase the supervision of people entering the compound, both Jews and Muslims," he said.
But Sheikh Azzam al-Khatib, head of the Islamic Waqf which runs the compound, rejected the idea.
"This is unacceptable to all Muslims. It cannot be installed," he told AFP.
The US State Department sharply condemned Israel's announcement of 200 new homes in the east Jerusalem settlement neighbourhood of Ramot.
"We are deeply concerned by this decision, particularly given the tense situation in Jerusalem," said spokeswoman Jen Psaki.
UN chief Ban Ki-moon demanded both sides do everything possible "to avoid further exacerbating an already tense environment".
On Wednesday, suspected Jewish extremists staged a pre-dawn arson attack on a West Bank mosque two days after Palestinian knife attacks killed a settler in the southern West Bank and an Israeli soldier in Tel Aviv.