Spain has said it will limit use of the AstraZeneca Covid-19 vaccine to people under 55, becoming the latest European nation to impose an age restriction on it.
The move echoes earlier decisions by a growing number of countries in Europe that have restricted the vaccine's use despite the European Medicines Agency approving its use last week for all adults.
"The public health commission, at a meeting on Friday and following scientific evidence, has approved setting as 55 the maximum age for people to get the AstraZeneca vaccine against Covid-19," the Spanish health ministry said in a statement.
Last week, the German vaccines authority advised against using AstraZeneca's vaccine for the over 65s, judging that there was "not enough data" on its effectiveness in this age group.
France followed suit on Tuesday and Austria, Belgium, Poland, Sweden and the Netherlands have taken similar steps.
Switzerland has called for "additional studies" and although Italy approved the jab, it recommended using an alternative vaccine for the over-55s.
The age controversy compounds a row over a shortfall in deliveries from AstraZeneca that has forced the European Union to recalibrate its vaccination strategy.
The AstraZeneca jab is the third vaccine to be approved by the EU after those developed by Pfizer/BioNTech and Moderna.
However, its efficacy is reported to be just 60%, compared with more than 90% for the others.
Spain has so far vaccinated nearly 1.7 million people and plans to have covered 70% of its population by the summer's end, a goal reaffirmed on Wednesday by the government despite shortages and delays in vaccine supplies.
Also on Wednesday, Health Minister Carolina Darias said Spain was "open" to the idea of using Russia's Sputnik V vaccine as long as it was approved by European regulators.
Spain has been hard-hit by the pandemic, recording over 61,000 deaths from nearly three million cases.