Estonia, Lithuania, Luxembourg and Latvia suspended the same AstraZeneca jab as a precautionary measure.
But while concerning, officials are unconvinced clotting is a direct result of the vaccine.
The European Medicines Agency (EMA) said there was “no indication” the jab had caused blood clots, adding it didn’t appear the batch in question was defective.
The Medicines and Healthcare products Regulatory Agency (MHRA), which approves vaccines in the UK, said blood clots are still relatively commonplace.