There is "no indication" the Oxford/AstraZeneca jab causes blood clots, according to the European Medicines Agency.
A full investigation is underway into the safety of the Covid-19 vaccine, after 10 European nations including Germany, France and Italy suspended its use over health fears.
Addressing a virtual press conference, agency head Emer Cooke said the body stood by its decision to approve the vaccine.
"We have pulled together an ad hoc meeting again today to help us evaluate these cases with all the surrounding information that the member states will have," Cooke said.
The review comes as the World Health Organization urged countries not to halt vaccinations.
The World Health Organization has urged countries to continue the rollout.
AstraZeneca says about 17 million people in the EU and the UK have received a dose of the vaccine, with fewer than 40 cases of blood clots reported as of last week — no more than the number of blood-clot incidents typically reported within the general population.
Results from the European Medicines Agency investigation are due to be released tomorrow.
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