Gaza received its first shipment of Covid-19 vaccines on Wednesday after Israel approved the transfer through its border with the Hamas Islamist-run territory, Israeli and Palestinian officials said.
Gaza, where 2 million people live, has reported more than 53,000 coronavirus cases and 538 deaths.
The shipment, sent by the Palestinian Authority from the occupied West Bank, included 2,000 doses of Russia's Sputnik V vaccine, enough to inoculate 1,000 people in a two-shot regimen.
"We will use the doses to vaccinate patients who had organ transplants and those who suffer kidney failure," Majdi Dhair, a Gaza health ministry official, told Reuters.
"Medical personnel will not be vaccinated this time as the shipment is not enough," Dhair said.
Shipment of the vaccine, via Israel, to Gaza had drawn criticism from right-wing Israeli politicians.
They had called on their government to make the transfer conditional on the release of two Israeli civilians believed held captive by the militant group and the return of the remains of two Israeli soldiers killed in the 2014 Gaza war.
But Israel, leading the world in the speed of its own vaccination programme, has also come under pressure from rights groups to do more to ensure vaccines reach Palestinians in territory it captured in the 1967 Middle East war.
Palestinian officials, blaming Israel, said a transfer planned for Monday had been cancelled.
Officials in the Palestinian Authority said they submitted the vaccine transfer request to Israeli defence authorities soon after receiving an initial shipment of 10,000 Russian doses in the West Bank on Feb. 4.
The delay highlights the challenges Palestinians face inoculating citizens across the West Bank and Gaza - two geographically-divided areas which are home to 5.2 million Palestinians.
Israel controls all entry and exit points to the West Bank and most of the coastal and land boundaries of the Gaza Strip, an enclave that Israeli troops and settlers left in 2005.