The number of new coronavirus infections in the past week jumped by about 55%, but the number of deaths remained stable, the World Health Organisation has said.
In the weekly WHO report issued on Tuesday night, the UN health agency said there were about 15 million new Covid-19 cases last week and more than 43,000 deaths.
Every world region reported a rise in cases except Africa, where there was an 11% drop.
The organisation said the extremely contagious Omicron variant continues to define the pandemic globally and is now crowding out the previously dominant Delta variant.
It said Omicron, which was first detected in southern Africa in late November, accounts for nearly 59% of all sequences shared with the largest publicly available global database of viruses.
The WHO said Omicron has proven to have a shorter doubling time, with increasing evidence it can evade immunity. It also noted that numerous studies suggest it is less severe than previous variants.
After a steep rise in Omicron cases in South Africa after the variant was detected, the epidemic quickly dropped and experts believe the wave has passed. The WHO said this week that after a continuous rise across Africa, cases fell this week for the first time.
Scientists in the UK and the US say there are early signs that Omicron may have peaked, but they are still uncertain how the next phase of the pandemic might unfold.
The WHO noted the Americas reported the highest-ever number of Covid-19 cases this week, with a 78% spike, mainly driven by the US.
The number of new cases in Europe rose by 31%, but there was a 10% drop in deaths.
The biggest jump in infections was noted in south-east Asia, where cases increased by more than 400%, with the largest numbers reported in India, Timor-Leste, Thailand and Bangladesh.
The numbers of deaths in the region fell by 6%.
The Omicron variant spreads even more easily than other coronavirus strains, and has already become dominant in many countries. It also more easily infects those who have been vaccinated or had previously been infected by other versions of the virus.
However, early studies show Omicron is less likely to cause severe illness than the Delta variant, and vaccination and a booster still offer strong protection from serious illness, hospital admission and death.