Wintry weather is forecast to tighten its grip in many parts of the UK this week with sub-zero temperatures plunging even lower than during the heavy snowfall of the past weekend. Weather forecasters predict the coldest nights of the year so far on Wednesday and Thursday, and temperatures are expected to fall as low as -20C in some areas.

Weather warnings remain in force across the UK as Britons are braced for temperatures to plummet as low as minus 16C. Snow, ice and fog yellow weather warnings are in force across the UK on Thursday, after snow and sleet caused disruption on Wednesday.