As Britain shivers in temperatures as cold as the South Pole, forecasters are warning there is more to come.

On the coldest night for 14 years the mercury dropped to -7.6F in the Scottish Highlands, with well below freezing temperatures elsewhere in the U.K.

Sky News' weather presenter Isobel Lang said there would be no break from the conditions.

"Biting northeast winds will set in across England and Wales later, and will persist all weekend," she said.

"There will be a significant wind chill. It will feel perishingly cold and there'll be more snow especially on Sunday across southern Britain."

The deep freeze left roads and pavements covered in sheet ice, making driving and conditions for pedestrians extremely dangerous.

Sky correspondent Michelle May in Woodford, Cheshire, said the roads were "extremely difficult."

"The roads are clear but really icy, and they've been like this for at least a week," she said.

As councils battle to keep roads open they are warning of dwindling grit supplies.

In Hartlepool, Essex and Leeds, officials have decided to only grit key routes, leaving many roads untreated.

Transport Secretary Lord Adonis said the situation was "as good as it could be at this stage" and said gritters had stopped treating motorway hard shoulders in an effort to save reserves.

The government has set up 'Salt Cell', an emergency body responsible for deciding who gets salt stocks, but Environment Secretary Hilary Benn admitted supplies were low.

He said: "We may face some difficult decisions about which roads are going to continue to be salted, because it looks as if the cold weather is going to last for quite some time yet."

There was better news on energy reserves as the National Grid lifted its Gas Balancing Alert.

It expects UK demand to hit a record high today but says supplies have been "consistently healthy" this week.

Overnight, temperatures in Manchester fell to 5F, with Glasgow reaching 18F, Cardiff 23F and London hovering just below 32F.

The lowest temperature in the Scottish Highlands came close to the -9.2F) currently at the southernmost part of the globe.

The record low for Britain of -16.9F) was recorded in Braemar in Scotland on January 10, 1982.

Conditions have been so poor in places that some villages have been cut off, including Princetown in Dartmouth.

Sky correspondent Katie Stallard, reporting from inside the village, said an air ambulance had landed in a garden to rescue an ill resident.

She said: "This is what it means to be stranded. Medical help is a long way away, and the firefighters in this case have been the first responders."