Mark Drakeford, first minister of Wales, has announced new measures for businesses to come into effect after Christmas to help curb the spread of infections.
From 27 December, nightclubs will have to close and a 2m rule on social distancing in offices will be introduced, alongside extra measures to protect customers and staff, such as one-way systems and physical barriers.
In a series of tweets, Drakeford said: “Delta will continue to be the main cause of coronavirus infections in Wales up to Christmas. But we are seeing cases of omicron increasing rapidly every day in Wales – and across the UK.
“We need a plan to keep us safe this Christmas and we need stronger measures to protect us afterwards, as we prepare for a large wave of Omicron infections.
“Omicron poses a new threat to our health and safety. It is the most serious development in the pandemic to date.
“It is one we must take seriously. We will continue to put in place proportionate measures to protect people’s lives and livelihoods.”