Two weeks after two deadly earthquakes struck Türkiye and neighboring Syria, only a trickle of UN aid has entered the opposition-held northwest of the war-ravaged country, with the slow pace sparking frustration and despair among victims.

The 7.7 magnitude and 7.6 magnitude quakes killed more than 46,000 people in Türkiye and Syria, including 5,800 in Syria, piling more misery on a population who activists say has been abandoned by the world in the midst of tragedy.

How does UN aid reach Syria's northwest?

More than four million people live in areas outside regime control in Syria's north and northwest and 90 percent of whom depend on aid to survive.

Yet the first UN aid convoy crossed into the area on February 9 - three days after the quake struck - and carried tents and other relief for 5,000 that had been expected before the earthquake.

The UN largely delivers relief to Syria's northwest via neighbouring Türkiye through the Bab al Hawa crossing - the only way for aid to enter without Damascus' permission.

With the road leading to Bab al Hawa briefly damaged after the quake and aid workers in the devastated areas also affected, international pressure mounted for relief to pour in.

On February 13, the United Nations said Damascus had allowed it to also use Bab al Salama and Al Rai crossings for three months.

Despite the additional crossings, relief workers say the UN aid deliveries remain insufficient.

Since the quake struck, the UN said it sent nearly 200 trucks to northwest Syria - less than the weekly average of 145 recorded in 2022 according to Doctors Without Borders (MSF).

Syria's White Helmets rescue group which operates in rebel-held areas have slammed the UN's slow response, calling it a "crime".

On February 12, UN relief chief Martin Griffiths acknowledged the body had "failed the people of northwest Syria".

Stephane Dujarric, spokesman for UN Secretary-General Antonio Guterres, said Monday that 10 aid trucks had crossed at the Al Rai border point.

"This is the first UN convoy through this border crossing since the Government of Syria agreed to its use for aid deliveries, which now brings us to three fully operating border crossings for the United Nations."

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How do aid groups send relief?

International aid groups are not bound by the UN's cross-border aid mechanism and can truck aid through other crossings with Türkiye's approval.

International organisations also provide funding to aid groups in the northwest to "buy what they need either from the local market or from Türkiye through commercial crossings", said Racha Nasreddine of ActionAid.

But with millions made homeless by the quake, stocks of blankets, food and tents were quickly depleted.

Although donations poured in, local groups struggled to secure necessities as prices of basic goods shot up at home while roads leading to Türkiye were damaged in the tremor, she said.

And while planeloads of foreign aid flooded regime-controlled areas after the quake, Syria's northwest was largely left to fend for itself.

Who is blocking relief to the northwest?

Although the regime of Syria's Bashar al Assad does not control crossing points with Türkiye, the United Nations sought its approval to use them.

Syria and its ally Russia have long insisted that all relief pass through regime-controlled areas and Moscow has threatened to veto the UN cross-border mechanism at past security council meetings.

Many aid groups say they do not trust Syrian authorities to dispatch aid to areas under rival control.

On February 10, the Assad regime said it approved the delivery of humanitarian aid directly from regime-held territory to opposition areas.

Nearly three million people, most of whom have been displaced by Syria's war, live in the Idlib region, while 1.1 million reside in areas of northern Aleppo.

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