The World Health Organisation says there were 21 million new coronavirus cases reported globally last week, the highest weekly number of COVID-19 cases recorded since the pandemic began.

The number of deaths was largely unchanged, at more than 50,000.

In its weekly assessment of the pandemic, issued late on Tuesday, the UN health agency said the number of new coronavirus infections rose by five per cent and the rate of increase appeared to be slowing; only half of regions reported an increase in COVID-19.

Earlier this month, the previous highest number of cases - 9.5 million - was recorded amid a 71 per cent spike from the week before, as the hugely contagious Omicron variant swept the world.

WHO said the biggest increase in cases was seen in the Middle East, with a 39 per cent rise, followed by a 36 per cent jump in Southeast Asia. Deaths increased in Southeast Asia, the Middle East and the Americas, but fell in other regions.

On Monday, WHO's director-general Tedros Adhanom Ghebreyesus cautioned against talk that the pandemic might be entering its "endgame," warning that conditions remain ripe for new variants to emerge, with vast swathes of unvaccinated people in some countries amid rapid virus transmission.

Still, Tedros said it might be possible for the world to exit the acute phase of the pandemic, if goals like immunising at least 70 per cent of each country's population are met later this year.