European Union Health Commissioner Stella Kyriakides has urged other countries manufacturing Covid-19 vaccines to contribute to global supply and facilitate the good functioning of supply chains.
"In the same vein, we call on companies involved in the vaccine manufacturing chain to release all available stocks and to respect agreements," Ms Kyriakides told an event organised by the World Health Organization (WHO) on the Access to Covid Tools Accelerator known as ACT.
The EU is the largest manufacturer of Covid-19 vaccines and the largest global supplier, having exported more than 40 million doses to more than 35 countries, she said.
It comes as German Chancellor Angela Merkel voiced support for EU chief Ursula von der Leyen's threat to block AstraZeneca vaccines produced in the bloc from being exported, ahead of a crunch EU summit on the escalating row.
"I support Commission President Ursula von der Leyen," said Merkel.
"We have a problem with AstraZeneca," she added.
European officials are furious that AstraZeneca has been able to deliver its UK contract in full while falling short on its supplies to the EU.
In her tough warning to the Anglo-Swedish pharmaceutical giant last Saturday, Ms von der Leyen said: "That's the message to AstraZeneca: you fulfil your contract with Europe first before you start delivering to other countries."
Taoiseach Micheál Martin told RTÉ's News at One yesterday that an export ban would undermine supply chains.
Mr Martin said he was very much against stopping vaccines manufactured in the EU from leaving the EU, adding that he believed it "would be very retrograde step" and "counterproductive".
The EU warning comes as the union struggles to speed up its Covid-19 inoculation campaign, just as many member states are facing a third coronavirus wave and renewed curbs on public life.
Ms von der Leyen said AstraZeneca had delivered only 30% of the 90m vaccine doses it had promised for the first quarter of the year.
Much of the frustration is over supplies to Britain, where the inoculation campaign has progressed at a much faster pace and where AstraZeneca also has production facilities.
Brussels has accused London of operating a de facto export ban to achieve its vaccine success, a claim furiously denied by Prime Minister Boris Johnson's government.
Britain has in turn voiced alarm over the EU's threat to halt AstraZeneca supplies leaving the continent.
Ms Merkel said both herself and France's Emmanuel Macron had spoken with Mr Johnson on the issue, and that a summit of EU leaders later this week will address the subject.
The board "expressed concern that AstraZeneca may have included outdated information from that trial, which may have provided an incomplete view of the efficacy data," a statement from the National Institute of Allergy and Infectious Diseases said.
