The South African rand fell against the dollar after a new variant was detected in the country.
The currency fell to as low as 16.2391 against the US dollar during the Asia trading hours on Friday and was last trading about 1.6% weaker at 16.2215 per dollar.
The Japanese yen strengthened against the US dollar as investors sought out safe-haven assets. The U.S. dollar index was at 96.712 as compared to levels below 96.5 seen earlier this week.
One currency analyst told CNBC that the big move in the rand may be due to fewer trades being made during Asia hours.
Adarsh Sinha, co-head of Asia rates and foreign exchange strategy at Bank of America Securities, said that the news of the new variant in South Africa is driving part of the price action.
The World Health Organization is monitoring a new variant of the virus that has many changes to the spike protein. The health agency is going to have a meeting Friday to discuss what it means for vaccines and treatments.
According to the WHO, the variant has been found in small numbers in South Africa.
We don't know a lot about this. We know that this variant has a large number of changes. The WHO technical lead on Covid-19 said in a Q&A that it can have an impact on how the virus behaves.
The United Kingdom temporarily suspended flights from six African countries.
Hannah Miao contributed to the report.
