Serbia has delivered 10,000 coronavirus vaccines to neighbour Bosnia and Herzegovina.
It comes amid a row over delayed shipments from the international COVAX scheme, which last week delivered its first vaccines to Africa.
Nevertheless, officials have admitted the COVAX rollout has been slower than expected in some areas due to issues with shipping and approval.
COVAX is the vaccine distribution plan by the European Union, World Health Organization (WHO), Gavi, and others, which intends to deliver vaccines to poorer countries, regardless of their ability to pay for them.
But while some richer countries such as Israel, the UK and the US have raced ahead of the rest of the world in vaccinating their populations, those reliant on COVAX have had to be patient.
Supporters have hailed a “historic” week for the programme - unprecedented in scope - to ship the vaccines developed in record time to fight the pandemic.
But while countries in Africa have now received more than 5.7 million doses, including four million in Nigeria, European countries outside of the European Union are still awaiting the first of their allocations to arrive.
Bosnia has threatened to sue the COVAX programme unless its vaccines arrive as agreed.
The 1.2 million jabs it has asked for would cover around a third of its population.
Members of the multi-ethnic Bosnia presidency on Tuesday discussed the delivery problems with WHO chief Tedros Adhanom Ghebreyesus.
Bosnia will sign what it described as “additional” documentation requested by vaccine producers, a statement issued after the video conference said. It added that Bosnia has met the conditions for the arrival and storage of the jabs.
'Act of solidarity' from Serbia
Serbia’s populist president, Aleksandar Vucic, flew to the Bosnian capital Sarajevo to deliver 10,000 AstraZeneca vaccines to the authorities there.
The delivery is enough for 5,000 people to receive both required doses.
Vucic described the move as an act of solidarity and urged closer cooperation among the Balkan countries.
“We have expected vaccines from the EU, we didn’t get them,” Vucic said. “We will thank them when we receive vaccines from the COVAX programme.”
Serbia launched its vaccination programme in January, mainly using China’s Sinopharm, along with Pfizer-BioNTech, Russia’s Sputnik V and AstraZeneca.
“President Vucic made us an offer at the moment when international mechanisms failed and we accepted it,” said Sefik Dzaferovic, the Bosniak member of the multi-ethnic Bosnian presidency.
The Croat representative, Zeljko Komsic added that "if even one of these 5,000 vaccines saves a life, then it’s worth it.”
Both Bosnia and Serbia have been seeking European Union membership. Serbia and the Bosnian Serbs have also forged close relations with Russia and China.
Delays to COVAX rollout
Dr Seth Berkley of Gavi, the Vaccine Alliance, admitted on Tuesday there had been hiccups in the COVAX project.
“Some of the timelines have slipped,” he said, adding, “the same number of doses will ultimately be made available.”
Ivory Coast and Ghana have started vaccinations this week, and Colombia received doses through COVAX on Monday.
Some 11 million doses are expected to be delivered this week — among 237 million doses due to be delivered to 142 countries and territories through the end of May.
That's a tweaked timetable: Last month, GAVI announced plans to distribute 336 million doses of the vaccine developed and produced by Oxford University and British-Swedish manufacturer AstraZeneca — a pillar vaccine in the COVAX programme.
COVAX is also to receive 1.2 million doses of a vaccine made and distributed by US pharmaceutical giant Pfizer and German partner BioNTech, which have already shipped doses by the millions to mostly wealthy countries that have bought it.
Berkley said Pfizer has required “additional work” from some countries seeking its vaccine, causing “a delay in rolling out that vaccine as compared to the aspirations we had.”
The Pfizer-BioNTech vaccine needs storage at ultra-cold temperatures, making rollout complex in hot countries and rural areas, for example.
He said South Korea received doses of that vaccine on Friday, but did not specify how many. He suggested more is to come from COVAX.
“Just keep in mind that it is very early days,” Berkley said. "We’re in the first week of doing rollouts now.”