Germany announced Thursday it would lift in early January strict travel rules for people arriving from countries hardest hit by the Omicron coronavirus variant.

All countries currently listed in the "virus variant" category, including the UK and several southern African nations, will be reclassified as "high risk" from January 4, said government health agency, the Robert Koch Institute.

The change eases a ban on entry for travellers who are not German residents or citizens, instead allowing anyone to enter as long as they observe quarantine and testing rules.

Germany introduced its "virus variant" travel category in a bid to stop new coronavirus strains that have not yet spread widely on its territory.

Only citizens and residents of Germany are permitted to enter from an Omicron variant country and are subject to a two-week quarantine, regardless of whether they are fully vaccinated or can provide a negative Covid-19 test.

By contrast, anyone can enter from a high-risk country as long as they provide a negative test on arrival.

Travellers from high-risk areas are exempt from quarantine if they have been fully vaccinated.

Germany has so far recorded 16,748 cases of Omicron but the real number is thought to be much higher due to delays in reporting over the Christmas period.

Health Minister Karl Lauterbach said on Wednesday that he expects a significant rise in the number of Omicron cases in Germany within "in a few weeks".