Omicron is now the dominant Covid-19 variant circulating in the European Union and European Economic Area (EAA), the bloc's health agency said on Friday.
"The transmission category for Omicron in the EU/EEA changed from community to dominant," the Stockholm-based European Centre for Disease Prevention and Control (ECDC) said in its weekly update on communicable disease threats.
The EEA includes Iceland, Liechtenstein and Norway.
The ECDC said Omicron, which was first discovered in South Africa, was now "dominant in the majority of EU/EEA countries", with a "78 percent pooled prevalence".
Covid is currently soaring across Europe, with cases increasing by nine percent in the region in the past week, according to an AFP database.
The World Health Organisation said last week that Omicron could infect half of all people in the region by March.