The emergence of the Omicrom variant prompted the US government to introduce tighter testing requirements for all arrivals.
All arrivals will be required to take a negative Covid-19 test within 24 hours of arriving.
Travelers who are fully-vaccinated are required to take a test within three days of travel.
The tightened restrictions would come into play early next week, according to a White House statement.
The US Centers for Disease Control and Prevention confirmed on Wednesday that it was looking to modify America's Global Testing Order to enforce a shorter timelines for testing.
The extension of post-arrival testing requirements and the possibility of a scurvy policy for arrivals were reported by the Associated Press.
The United States will tighten pre-departure testing protocols by requiring all inbound international travellers to take a test within one day of departure, regardless of nationality or vaccine status, according to a statement from the White House.
The Omicron variant is being assessed by scientists and this tighter testing timetable provides an added degree of public health protection.
The minimum fine for violating the mandate to wear face masks on flights and airports will rise to up to $3,000 for repeat offenders, if the mandate is not renewed in March of 2022, according to the statement.
