Britain's Big Freeze continues to grip parts of the country with forecasters predicting more heavy snowfalls for later in the week.

The blizzards are thought to have cost the economy as much as £3.5 billion as London and other major cities ground to a halt.

Millions of adults were forced to stay off work for a second day as around 6,000 schools remained closed in Bradford, Birmingham, Bristol, Surrey, Kent, Hertfordshire, Essex, London, Devon, Cornwall, Gloucester, Oxfordshire, Buckinghamshire, Berkshire and the Borders.

Wales was also badly affected with hundreds of schools closed and bus services in South and West Wales largely cancelled.

Schools Secretary Ed Balls said any inconvenience to parents as a result of school closures was "really regrettable".

"I have a huge amount of understanding for those parents for whom life has been difficult, but in the end these decisions are made by the heads of our local authorities, they have to make the right decision often in difficult circumstances, and I think they have been doing it right."

Stephen Alambritis, from the Federation of Small Businesses, said: "One of the world's biggest economies should not be grinding to a halt."

But further disruption is likely with another wave of snow expected to sweep from south to north through Wednesday night and Thursday.

Two climbers who fell to their deaths on a treacherous part of Mount Snowdon, and whose bodies were discovered on Monday morning, were earlier identified as brothers James and Christopher McCallion.

They had been reported missing by family members on Sunday after failing to return home to Bristol.

Weather forecaster Paul Knightley said Scotland is the only place likely to see snow on Wednesday but warned that a new band of low pressure - bringing snow, sleet and rain - will start moving across southern counties of England, reaching parts of the Midlands and southeast Wales by Thursday morning.

He said: "Indications are that the heaviest snow is likely to be across the south Midlands and northern Home Counties, with the possibility of over 20cms of fresh snowfall in places.

"However, southeast of an approximate line from the Isle of Wight through London, any snow is expected to turn to rain, as somewhat less cold air brushes past south east England."

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