It is important for them to understand that "not returning home at this time is also a contribution to pandemic prevention in Vietnam," officials from the three ministries said at a meeting with the National Steering Committee for Covid-19 Prevention and Control on Thursday.

They made the decision after the Ministry of Foreign Affairs reported there was great demand for returning home for the festival, which falls in the middle of next month.

Without providing specific figures, the ministry had said many ethnic Vietnamese living abroad wish to visit the country not only for Tet, by far the biggest and most important festival for Vietnamese, but also to escape the pandemic, which is basically under control in Vietnam.

In addition, their visas have already expired and they have encountered financial issues, said the ministry.

The committee said it is critical that borders are sealed to prevent illegal entrants.

It said 46 countries have started vaccinating people against Covid, but to vaccinate the entire population and achieve herd immunity would take long while the new and more contagious strains have been spreading rapidly to various countries.

The health ministry said it is best for Vietnam now to continue with the methods it has been applying since the first outbreak, which include preventing infection, detecting cases of infection, contact tracing, and locating stricken areas and lock them down.

Earlier this month Vietnam reported its first case of the U.K. Covid variant through a woman who returned home from Britain in December.

Vietnam still remains closed to all international commercial flights and banned flights from places that have recorded the new variants.

It has gone 49 days without local transmission.

The new strain in the U.K. has spread to 50 countries and territories while the one found later in South Africa has reached 23.