WASHINGTON - New rules requiring international air travellers arriving in the US to obtain a negative Covid-19 test within one day of travel will take effect on Monday at 12.01am (1.01pm Singapore time), US officials confirmed on Thursday (Dec 2).
Under current rules, vaccinated international air travellers can present a negative test result obtained within three days of their day of departure.
Unvaccinated travellers currently must get a negative Covid-19 test within one day of departure.
The Centres for Disease Control and Prevention (CDC) said on Thursday that beginning on Monday, "all air travellers, regardless of citizenship or vaccination status, will be required to show a negative pre-departure Covid-19 viral test taken the day before they board their flight to the United States".
The tighter testing timeline "provides an added degree of public health protection as scientists continue to assess the Omicron variant", the White House said in a fact sheet released on Thursday.
The CDC is expected to give airlines a three-day grace period to allow for some travellers to return to the US with tests taken outside the one-day window.
The administration is considering whether to grant temporary exemptions for about two dozen countries where access to same-day testing is limited, but the details are still being finalised. Those exemptions could last for only about a week.
On Monday, the White House said it would bar nearly all foreign nationals from entering the US from eight southern African countries over fears of the spread of the Omicron variant, but has not extended those travel restrictions to other countries where the new variant has been discovered.
The US' top infectious disease official, Dr Anthony Fauci, said on Wednesday that he viewed the restrictions on the eight countries as a "temporary measure".
White House spokesman Jen Psaki said on Thursday that she would not "expect the lifting of restrictions before we know more about the variant".
"We will continue to evaluate if additional restrictions need to be put in place," she added.