United Nations Secretary-General Antonio Guterres on Thursday urged the Security Council to authorize the opening of new cross-border humanitarian aid points between Turkey and Syria to deliver UN aid to earthquake victims.

Some 4 million people living in the rebel-held areas of northwest Syria have been relying on humanitarian aid transported via the only Bab al-Hawa crossing as part of a cross-border aid operation authorized by the UN Security Council nearly a decade ago.

Three ancient cities suffered widespread destruction in Monday's massive earthquake in Turkey and Syria: Antakya, Sanliurfa and Aleppo.

Here are some key facts:

- Antakya/Antioch -

Antakya, a city of around 250,000 people in south-central Turkey, large parts of which have been reduced to rubble, was once the ancient city of Antioch which rivalled Alexandria as a major centre of early Christianity and was a key staging point on the Silk Road.

Russia's top diplomat Sergei Lavrov held talks in Khartoum Thursday with Sudanese officials, pledging support for their call to lift long-standing UN sanctions on the African nation.

Lavrov's two-day visit is part of Russian efforts to shore up influence on the African continent amid broad international attempts to isolate Moscow following its invasion of Ukraine last year.

Widowed and homeless, Duaa Ghadban lost everything in a powerful earthquake, forcing her to take shelter in a camp for people displaced by war in Syria's northwest.

The 7.8-magnitude quake early Monday has killed more than 19,000 people in Turkey and Syria and flattened entire blocks over residents in their sleep.

Syrians displaced by the country's 12-year war, living in tents along the Turkish border, were largely spared the damage.

Hopes faded Thursday of finding more survivors after the earthquake that killed nearly 20,000 people in Turkey and Syria, as the first UN aid reached Syrian rebel-held zones.

Bitter cold has hampered the four-day search of thousands of flattened buildings and threatened the lives of many quake victims who are without shelter and drinking water.

Relatives were left scouring body bags laid out in a hospital car park in Turkey's southern city of Antakya to search for missing relatives, an indication of the scale of the tragedy.

An aid convoy reached rebel-held northwestern Syria Thursday, the first since a devastating earthquake that has killed thousands, an official at the Bab al-Hawa border crossing told AFP.

The 7.8-magnitude quake early Monday has killed nearly 20,000 people in Turkey and war-ravaged Syria, according to officials and medics in the two countries, flattening entire neighbourhoods.

"The first UN aid convoy entered today," said Mazen Alloush, media officer at the crossing.

Two dozen children from northern Cyprus and some of their parents were on a school trip to join a volleyball tournament in Turkey when a massive earthquake hit their hotel.

The only thing that remains of it now is a flagpole.

Located on the main boulevard of Adiyaman in Turkey's devastated southeast, the hotel was completely flattened. Dozens of other buildings on both sides of the long road have suffered the same fate.

Syria's politically isolated President Bashar al-Assad has received calls and aid from Arab leaders since a devastating earthquake Monday, a momentum analysts say he could leverage to bolster regional support.

The 7.8-magnitude pre-dawn quake has killed more than 16,000 people in Turkey and neighbouring Syria, already reeling from over a decade of conflict and years of economic sanctions.

Cracks have emerged within Israeli Prime Minister Benjamin Netanyahu's hardline government, with a row over the demolition of a settlement outpost in the occupied West Bank testing the fledgling coalition.

Netanyahu vowed in December to expand settlements across the West Bank, as he returned to power at the helm of the most right-wing government in Israeli history.

But a split over policy on the ground surfaced last month, when Israeli troops moved in to dismantle a wildcat outpost in the northern West Bank dubbed Or Haim on orders from Defence Minister Yoav Gallant.

Rania Zaboubi scours body bags laid out in the car park of a hospital in southern Turkey in search of her uncle who went missing after Monday's massive earthquake.

"We found my aunt, but not my uncle," she says in a choked voice.

The Syrian refugee says she lost eight members of her family in the tragedy that has so far claimed the lives of at least 16,000 people in Turkey and neighbouring Syria.