From Thursday, all travellers entering Singapore from Category II, III and IV countries will need to produce a negative pre-departure Covid-19 polymerase chain reaction (PCR) test result taken within 48 hours before leaving for Singapore, said the Ministry of Health (MOH) in a statement yesterday.

Previously, the requirement had been for the test to be taken within 72 hours before travel, and applied to those coming from Category III and IV countries. The new requirement takes effect at 11.59pm on Thursday, along with other changes to border measures for travellers from a number of countries and regions.

Singapore's differentiated border measures for different countries were introduced on Aug 19.

According to MOH, Category I comprises places with the lowest risk of Covid-19 transmission, Category II countries are those with similar Covid-19 risk profiles to Singapore, those in Category III are deemed to be at higher risk of Covid-19 infections, and Category IV comprises the remaining places with the highest risk of Covid-19 infection.

MOH has placed several countries in new categories.

South Korea, previously in Category III, has been added to Category II. Other countries in Category II include Australia, New Zealand and Germany.

From Thursday, travellers from South Korea will need to take a pre-departure test, be tested on arrival, serve a seven-day stay-home notice (SHN) at their place of residence and do a Covid-19 PCR test at the end of their SHN.

Croatia, Egypt, Finland, Malta, the Netherlands, Poland, Saudi Arabia and Sweden, previously in Category IV, are now in Category III.

Travellers from Category III countries who are fully vaccinated may apply to opt out of serving their 14-day SHN at dedicated facilities, and do so at their place of residence instead, as long as they were in their countries for 21 days prior to their travel to Singapore, and isolating alone or with members of the same household.

Travellers who are unvaccinated or do not fulfil any of the above conditions will have to isolate in dedicated SHN facilities.

"As the global situation evolves, we will continue to adjust our border measures in tandem with our road map to becoming a Covid-resilient nation," said an MOH spokesman.

To keep up with the latest changes in border measures, members of the public can go to the SafeTravel website at https://safetravel.ica.gov.sg/