The European Union's drug watchdog said Thursday that it is assessing the possible use of Moderna's Covid vaccine for children aged five and under, the only group not yet eligible for the jab in most countries.

"We have just started the evaluation of an application from Moderna to extend the use of Spikevax to children from six months of age to five years," said Marco Cavaleri, head of anti-infectives and vaccines at the European Medicines Agency (EMA).

"This is the first application for this young age group," Cavaleri said.

In February, the EMA's human medicines committee had already recommended granting an extension of indication for the Spikevax vaccine Spikevax to include use in children aged six to 11.

The jab, developed by US-based Moderna, had already been approved for adults and children aged 12 and above.

The Amsterdam-based EMA has so far approved five vaccines for use in the EU: Pfizer and Moderna, which use messenger RNA technology, AstraZeneca and Johnson & Johnson, which use viral vector technology, and Novavax, which is based on a spike protein produced in a laboratory.