The National Centre for Hydro-meteorological Forecasting said northern areas will receive another blast of cold in the next few days, especially in mountainous areas, where temperatures could dip as low as -1 Celsius. On Christmas night temperatures in the delta region are expected to be as low as 7-8 Celsius.

The ongoing cold spell has already caused damage to many crops and livestock in Cao Bang Province.

Nong Van Tau, a farmer in Trung Khanh District, where temperatures reached 0 Celsius, said, "This long cold spell is giving us a lot of problems. Bulls and cows are dying and most farmers are unable to leave home early in the morning and have to wait until sunrise. We're also late in preparing for the next crop."

Older locals have said that these temperatures are the coldest they can remember. In several mountainous districts, they also complained of both frost and acid rain harming their farms.

Hoang Van Tien, head of Trung Khanh District Department of Agriculture and Rural Development, said when the cold spell started, they sent people to guide the farmers on how to protect themselves and their livestock. Even though several weak and old buffaloes have died, they have not suffered from major damages, he added.

"On the other hand, tobacco farms were severely impacted. We don't have a firm estimate of the losses yet, but we're monitoring the situation continually," he said.