New restrictions are in place from today in Scotland, Wales and Northern Ireland while ministers in England are not expected to discuss further measures until at least Monday.
Jenny Harries, head of the UK Health Security Agency, said the impact on society of Omicron will be crucial despite mounting evidence that it is generally milder than the Delta strain.
Jeremy Farrar, a former SAGE member, pointed out that while another booster is already being mooted in the UK, many around the globe have yet to receive a first jab.
Hospitality and business leaders today led fury at politicians in Scotland, Wales and Northern Ireland for imposing much tougher Covid-19 restrictions than England.