The WHO says the highly infectious mutation of COVID-19 first recorded last month in the UK has spread to dozens of countries.
According to its latest weekly report, the UK variant which was first discovered on December 14th, has been found in 50 countries, territories and areas so far.
The agency added that the South African strain has been found in 20 different countries.
Raising extra alarm, the WHO noted the geographical spread of both variants is likely underestimated.
This comes as scientists at the Ohio State University Wexner Medical Center and College of Medicine have discovered a new variant.
In an official press release Wednesday, the researchers say the new variant carries a mutation identical to the UK strain, but likely arose in a strain already present in the U.S.
However, the researchers also report on the evolution of another U.S. strain that acquired three other gene mutations not previously seen together.
This means, two new strains may be spreading in the U.S.
Health officials say the new variant was found in a patient from Ohio, but they do not yet know the prevalence of the strain within the population, or if it has been spreading.
However, the evolving strain has already become the dominant virus in Columbus.
So far, scientists believe the new U.S. variant is similar to the UK variant, in that it's likely more infectious.
France continues to struggle with the UK variant.
The country's health ministry reported 19,753 new cases on Tuesday, some 35-hundred more than the previous day.
Health officials there say an estimated one percent of all cases in France are linked to the UK variant.
Despite the massive surge, France's top scientific adviser says there's no need to close French schools.
Russia, which is also trying to contain the new UK variant, has extended a ban on flights to and from Britain until February 1st.
Russia has had the ban in place since December 22nd.
Lee Seung-jae, Arirang News.