Large New Year's Eve celebrations will not be allowed due to the discovery of a second Omicron variant case in the country, said Health Minister Khairy Jamaluddin.
The second case is an eight-year-old who arrived from Nigeria via Qatar on Dec 5.
Mr Khairy said only small and private New Year's Eve and Christmas gatherings will be permitted.
"New Year's Eve and Christmas celebrations with family members and friends are allowed for now.
"However, Covid-19 tests must be done before attending these events," he told reporters in Parliament.
Meanwhile, the National Unity Ministry said Christmas choirs would be allowed but they must adhere to social distancing and mask-wearing.
"Visiting will be allowed for fully vaccinated people only. Carolling from house to house will not be allowed and Christmas Day stalls are dependent on the jurisdiction of local authorities," it said in a statement.
These curbs will be enforced on Dec 24 and 25.
Mr Khairy also said the vaccination status of those required to get their Covid-19 booster shot will be deemed "incomplete" if they fail to get their shots by February next year.
"If these... individuals still have not got their booster shots after February 2022, their vaccination status will be changed to 'incomplete'," he said.
He said those whose status has been changed to "incomplete" would not be able to enjoy the benefits of those who are deemed to have completed their vaccination.
Sinovac vaccine recipients are among those who must get booster shots by the February deadline.
Meanwhile, those above 60 years old, irrespective of vaccine type, will also be required to get their booster shot.
Mr Khairy said this was in line with the recommendation by the World Health Organisation's Strategic Advisory Group of Experts.
He added that Malaysia's Covid-19 Immunisation Booster Task Force had approved and adopted the recommendation on Dec 8.
Mr Khairy said the vaccines by Pfizer-BioNTech, Sinovac and AstraZeneca have been approved for use as booster shots currently.
He added those above 18 should also get their booster shots.
Booster shots started nationwide on Oct 13 for fully vaccinated individuals to ensure the immunity received after completing their doses can be maintained for an optimal period, especially against the Delta variant.
Last month, Mr Khairy stressed that Malaysia could face a new wave of Covid-19 infections if the administration of booster doses was not accelerated.
In a tweet later yesterday, he said that in line with the government's effort to ramp up the booster vaccination drive, mega vaccination centres will be reopened starting with the Klang Valley.
"All (those) 60 and above or Sinovac recipients must get a booster latest by February 2022 to keep (their) fully vaccinated status.
"You will get your booster appointment on MySejahtera 180 days after the second dose (Pfizer-BioNTech or AstraZeneca) or 90 days after the second dose (Sinovac)." - Straits Times