The World Health Organisation (WHO) has made it clear that it does not expect widespread vaccinations against COVID-19 until the middle of 2021, stressing the importance of rigorous checks on their effectiveness and safety.

"We are not expecting to see widespread vaccination until the middle of next year," spokeswoman Margaret Harris told journalists at a briefing in Geneva.

"This phase 3 must take longer because we need to see how truly protective the vaccine is and we also need to see how safe it is," she added referring to vaccine clinical trials.

Earlier, the head of WHO said that that his agency was setting up a review committee to evaluate the performance of its International Health Regulations (IHR) during the COVID-19 pandemic.

Moreover, WHO had also stressed earlier that the emergency authorisation of COVID-19 vaccines requires a "great deal of seriousness and reflection", after the United States announced it was considering fast-tracking candidate drugs.

Although every country had the right to approve drugs without completing full trials, "it is not something that you do very lightly", WHO chief scientist Soumya Swaminathan told a news conference.

The WHO`s preferred approach would be to have a full set of data that could be used for the pre-qualification of vaccines, Swaminathan said. The WHO would then consider the efficacy and safety of each drug on a case by case basis, she added.