Snow and ice has closed schools across north east Scotland on the first day back for pupils after the festive break.

More than 70 schools in Aberdeenshire and several in Moray and the Highlands have been hit by overnight snowfall and poor road conditions.

Yellow weather warnings are in place in the central belt, south and north east until 12:00, with another warning along the west coast until 11:00.

The Met Office expected as much as 20cm of snow in higher areas of the Borders and southern part of the Lothians, after temperatures in the Highlands plummeted to as low as -13C overnight.

Sunday night was the coldest night of the winter so far in the UK, according to the Met Office with temperatures at Loch Glascarnoch in the northwest Highlands falling to -13.3C.

About 10cm of snow was expected in areas of Aberdeenshire, Moray, north Angus, north Perthshire and Strathspey and Badenoch above 200 metres.

Rain or sleet is more likely to fall in the east of Scotland.

Forecasters urged anyone leaving their homes over the next 48 hours to exercise caution when walking outside due to ice on paths and pavements.

Transport Scotland urged commuters to plan ahead and check advice online before they travel.

ScotRail had been forced to cancel several services and close the Far North Line between Inverness and Dingwall last week due to landslips and flooding.

David Ross, ScotRail’s communications director, told BBC Scotland News the operator was “not taking any chances” as commuters returned to work.

He said: “Network Rail will have colleagues out at locations around the country to de-ice the railway and they have also got special winter trains that can check lines and clear them of snow if required.

“The network is coping very well. We did have some challenges in the north of the country and those have been resolved.”

In Glasgow, Amey, which operates the gritting machines, said about 24,000 tonnes of road salt and 231,000 litres of brine had been stocked up at their Polmadie depot to tackle the freeze.

Amey gritter driver George McLellan said: “We’ve got guys on call 24 hours so when you get the call, it’s all hands to the pump, into the yard, get your grit loaded up and go out and patrol and grit the roads.

“The challenges in this job are mainly the traffic during busy periods – to try and get the grit down.

“I think the worst is yet to come.”

Network Rail Scotland, which maintains and repairs the tracks, said it had made preparations to deal with the weather.

It said: “Locomotives with ploughs are standing by at strategic locations, ready to clear tracks if it’s needed.

“Snow showers remain likely across parts of the West Highland Line and lines out of Inverness for the first half of the week.”

Ferry operator CalMac warned a number of services could face disruption, with all sailings on the Mallaig to Oban route cancelled for the day.