The WHO said it was capitalising on the chance brought about by the suspending of sanctions to carry out some rapid procurement and revitalise Syria's shattered health services.
The UN health agency called on Syria's warring factions to see the earthquake as an opportunity to end the civil war for good.
The massive 7.8-magnitude tremor on February 6 has killed more than 42,000 people in Turkey and more than 3,600 in Syria, while the WHO said more than 125,000 have been injured.
Damascus has been hit by more than a decade of economic sanctions, and while they were not designed to impede aid, they were blamed by some for the slow arrival of assistance after the quake.
The United States has since temporarily lifted some sanctions, hoping to ensure that aid moves as quickly as possible to those affected.
"WHO is moving very rapidly right now, together with our partners, to take advantage of this pause in the sanctions," Richard Brennan, the WHO's Eastern Mediterranean regional emergency director, told a press conference.
"We have already started ordering equipment and supplies and we are working with UN partners on a collective approach to take advantage of the pause," he said from Gaziantep in southern Turkey, having returned from northern Syria.
Medicines, vaccines, X-ray machines and surgical tools were needed, he added.
"We will be moving very rapidly to do the procurement, capitalising on this important opportunity that we have."
Four planes filled with supplies have flown into Syria since the earthquake.
The Syrian conflict started in 2011 with President Bashar al-Assad's brutal repression of peaceful protests, and escalated to pull in multiple foreign powers and global jihadists.
Nearly half a million people have been killed, and the conflict has forced around half of Syria's pre-war population from their homes.
WHO chief Tedros Adhanom Ghebreyesus called on the warring factions to use the earthquake as a chance to come together and resolve the civil war.
"Warring parties now should use this earthquake as an opportunity to talk to each other and bring a political solution," he said.
"The Syrians actually believe that the earthquake is a lesser evil. It's another evil but a lesser evil compared to the 12 years of conflict, but not only that: the displacement, the economic meltdown.
"Anybody can see through what kind of hell the Syrian people are passing."
He said seven hospitals and 145 health facilities in Syria have been damaged, many in the northwest.
In Turkey, at least 15 hospitals had been damaged, with many health facilities also affected.
"WHO calls on the global community to support the response and provide hope to those who are grieving, traumatised and fearful about the future," Tedros said.
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