World Health Organisation experts have cautiously backed delaying second injections of the Moderna coronavirus vaccine in some situations, as they did for the Pfizer-BioNTech jabs.

The WHO's Strategic Advisory Group of Experts on Immunisation (SAGE) also insisted international travellers should not be prioritised for any Covid-19 jabs for the time being.

The WHO's vaccine advisory group said it was best to respect the tested intervals between doses of 21 days in the case of the Pfizer-BioNTech vaccine and 28 days for Moderna.

Head of the SAGE, Alejandro Cravioto, warned in a virtual press briefing though that “the evidence we have does not go beyond that” six-week cut-off.