With the festive season round the corner, the authorities will step up checks and enforcement on the next few weekends, Education Minister Lawrence Wong told the media yesterday.

More safe distancing ambassadors will be deployed, and they will be at hot spots and popular areas around the island together with enforcement officers.

Singapore cannot afford to let its guard down, cautioned Mr Wong, who co-chairs the multi-ministry task force on Covid-19.

"I would again remind and encourage everyone, just do your part, comply with the measures. Do not push the boundaries. This is not the time to let our guard down... to think that Singapore is very safe and therefore we can afford to push the boundaries, relax and just enjoy ourselves with large gatherings," he said.

Last week, Prime Minister Lee Hsien Loong announced that Singapore will enter phase three of its reopening on Dec 28.

But just yesterday, border measures had to be tightened for some travellers from Britain and the Australian state of New South Wales.

This comes as recent reports surfaced over a potentially more contagious strain of the Covid-19 virus circulating in Britain, causing officials there to put in place more stringent restrictions, including imposing a new lockdown in London.

The restrictions on travellers from New South Wales follow a cluster of cases centred on two dining and entertainment venues in a Sydney suburb.

Mr Wong stressed that even if some people are not caught by the enhanced checks and enforcement - such as people in large gatherings where "I close the doors... no one will know" - they ultimately endanger themselves and their families.

"The checks are not going to be perfect. Even if we fail to catch some people who may have committed such breaches, at the end of the day, the people who are doing so are taking risk upon themselves," he said.

"They are risking the health of themselves and their family members because I am sure the virus is still circulating around in our midst, in a hidden way, in a very low level of transmission - cryptic transmission, if you call it - but it is happening."

Five food and beverage (F&B) outlets have already been ordered to close, while 16 other outlets and 36 individuals will be fined for breaching safe management measures, said the Ministry of Sustainability and the Environment yesterday.

The breaches were uncovered during stepped-up enforcement checks over the past weekend.

The establishments had allowed groups of more than five to sit together or intermingle. Some served and allowed the consumption of alcohol past 10.30pm.

The ministry stressed last Friday that while many may wish to meet up with family and friends over the festive period, social gatherings in groups of more than five outside an individual's residence are not allowed.

F&B outlets must not accept bookings from groups that are larger than five, even if they are split across multiple tables. Intermingling between groups is also prohibited.

Mr Wong said that while the authorities will continue to monitor the situation at the borders, within Singapore, people have to continue to take the pandemic seriously.

"Everyone must do their part within the community too to stay alert and vigilant, recognising that the threat is not over and we all have a part to play to complete our mission together."