The UK has administered more than 31 million first vaccine doses, using both the Oxford-AstraZeneca and the Pfizer-BioNTech jabs. The EMA is expected to announce updated advice on the issue on April 7.
British regulators said they have identified 30 cases of rare blood clot events associated with the AstraZeneca vaccine but stressed the benefits of the jab in preventing coronavirus outweigh any risks.
The UK medical regulator said Saturday that out of 30 people who suffered blood clots after receiving the Oxford-AstraZeneca vaccine, seven have died. It did not disclose any information about their ages or health conditions.
The reports represented 25 more cases than Britain's medicines regulator had previously received, going some way toward addressing a mystery that has hung over safety concerns about the vaccine: why Britain had not observed the same phenomenon that has been seen in continental Europe, driving countries including France, Germany and Sweden to stop giving the shot to younger people, who are believed to be at higher risk from the rare clotting events.
The Medicines and Healthcare products Regulatory Agency said it had received no blood clot events following use of Pfizer-BioNTech vaccine.
America's leading expert on infectious diseases, Dr Anthony Fauci, has said the United States may not need the AstraZeneca vaccine against coronavirus even if the country's Food and Drug Administration (FDA) authorises its use.
Possible complications with the rollout of the AstraZeneca vaccine could further slow the already delayed inoculation drive in Australia.
Professor Adam Finn, from the University of Bristol, said: "The report states that these cases are being very carefully investigated to better understand whether or not they may have any causal relationship with vaccination".
On Thursday, it put the count at 22 reports of cerebral venous sinus thrombosis, an extremely rare brain clotting ailment, and eight reports of other clotting events associated with low blood platelets out of a total of 18.1 million doses given. Meanwhile, Australia on Saturday said it would continue to use the vaccine after one case that highlighted concern over blood clots.
"That's still up in the air", said Fauci when asked whether the USA will use the AstraZeneca vaccine doses.
The Netherlands on Friday halted vaccinations with the AstraZeneca jab for people under the age of 60 after five new cases among women, one of whom died.