Five EU member states on Saturday called for a summit meeting on the "fair distribution" of vaccines developed for the novel coronavirus pandemic.
Leaders of Austria, Czech Republic, Bulgaria, Slovenia and Latvia sent a letter to European Commission President Ursula von der Leyen and European Council President Charles Michel, requesting a meeting on vaccine distribution throughout the bloc.
In the letter published by the Austrian media, they asked that deliveries of doses by pharmaceutical companies to EU member states be fulfilled on an equal basis following the pro-rata population key.
Austrian Chancellor Sebastian Kurz in a Twitter post on Friday questioned the issue of equal distribution of vaccines, adding that the "last few weeks have shown that deliveries are currently not being made according to population keys and that this is set to intensify in the coming months."
"If the distribution were to continue in this way, it would result in significant unequal treatment - which we must prevent. All 450 million Europeans must be given the chance to return to normality by the summer," he said.
On Saturday, Kurz also announced on Twitter that the letter was sent to top EU authorities by the leaders of five states.
Meanwhile, an EU official confirmed that the bloc was already planning a summit set for March 25 and 26, noting that the COVID-19 coordination will again be addressed by the 27 members during that meeting.
In a written statement, the European Commission said the allocation of doses under the Advance Purchase Agreements has followed a "transparent process."
The EU signed the Advance Purchase Agreements with six vaccine producers -- Pfizer/BioNTech, Moderna, AstraZeneca, CureVac, Johnson & Johnson, and Sanofi/GlaxoSmithKline -- to purchase 2.6 billion vaccine doses.
"The Commission agrees with recent statements by several Member States that the most equitable solution for the allocation of doses of vaccines is on the basis of a pro-rata of population of each Member State. This is the solution that the Commission proposed for all Advance Purchase Agreements. It is a fair solution as the virus strikes equally everywhere, in all parts of the EU," said the statement.
"Member States decided to depart from the Commission's proposal by adding a flexibility which allows agreeing on a different distribution of doses, taking into account the epidemiological situation and the vaccination needs of each country. Under this system, if a Member State decides not to take up its pro-rata allocation, the doses are redistributed among the other interested Member States," it added.
The statement also underlined that a pro-rata basis distribution again depends on the decision of EU members.
