Dubai's authorities will not allow travellers who have been in South Africa or Nigeria to enter the emirate.
In a travel advisory, Emirates Airline said the decision covered any UAE resident, tourist or transit passenger who had been in either country in the past 14 days.
Emirates airline flights to South Africa and Nigeria were already suspended and will remain so until at least March 10.
This latest move came amid increasing concern about the South African variant of coronavirus.
The strain is transmitted from person to person more easily and most of the existing vaccines are less effective against it.
"You will not be able to enter Dubai if you have been in or transited through South Africa or Nigeria in the last 14 days before travelling to Dubai," the carrier said on its website.
"This is not applicable for UAE nationals who are returning to the UAE and members of diplomatic missions.
"Members of diplomatic missions travelling from Nigeria must present a negative Covid‑19 PCR test certificate from one of the authorised laboratories in Nigeria."
Low-cost partner flydubai carried the same advisory on its website.
Less is known about the Nigerian strain that the South African variant.
The strain, known as B.1.525, was first detected in mid-December in Nigeria. It was soon found in cases in the UK, France, and other countries. As of mid-February, researchers from University of Edinburgh had found two cases in Wales and 36 in England in genome samples that dated back to December.
It has not yet been added to the UK's 'variants of concern list' but further study is ongoing.
Dubai has tightened restrictions in recent weeks in a bid to contain the virus, including reducing the capacity of venues such as hotels, cinemas and sports complexes.
Yesterday, the Islamic Affairs and Charitable Activities Department in Dubai announced it had cancelled all permits for Ramadan tents in the emirate this year to prevent large gatherings.