Drivers in Scotland and northern England have been urged not to travel, as snow storms hit parts of the UK for a third day.

Police Scotland say travel conditions across much of the country are "extremely dangerous", following heavy snow.

A Met Office amber warning, meaning "be prepared", was lifted at 05:00 GMT.

It is believed to be the first time the "do not travel" warning has been issued since the high winds of January 2013.

The Met Office also has a yellow warning for very strong winds - including gusts of 65 -75mph - in place for much of England and Wales until 09:00 GMT.

Yellow warnings for snow and ice remain in place for parts of Scotland, Northern Ireland and northern England.

'Delaying travel'

Police Scotland are advising drivers not to use roads in Dumfries and Galloway, East Lothian, Edinburgh, Midlothian, West Lothian, Scottish Borders, East Ayrshire, South Ayrshire, Renfrewshire, South Lanarkshire and North Lanarkshire.

A force statement said: "If you do travel, you will experience delays of several hours or more.

"Congestion caused by vehicles may restrict emergency, recovery or winter maintenance vehicles from providing essential assistance or clearing roads.

"Drivers of HGVs should drive with extreme caution and be aware that you may be requested to park at a suitable position by the police.

"No-one should ever place themselves at risk on the road and it may be worth considering making alternative arrangements such as delaying travel until conditions improve or using public transport."

Transport Scotland urged drivers to avoid a repeat of Tuesday night when many were stuck for up to 11 hours on the M74 in South Lanarkshire and Dumfries and Galloway.

Scottish Borders Council said no schools would open in its area on Thursday, with 15,000 pupils missing lessons.

A total of 26 schools were also shut in Dumfries and Galloway on Wednesday, affecting 4,000 students.

In the Highland Council area, nearly 150 schools and nurseries were shut or partially closed, affecting 15,000 pupils.

Nearly 30 schools and nurseries were closed in South Lanarkshire and there are also a number of schools shut in East Ayrshire, Stirling, Falkirk and Perth and Kinross.

Scotland's Transport Minister Humza Yousaf has said the authorities would be "tested to our limit".

A guide to travel warnings

Travel conditions are graded at four levels by police and transport officials depending on the severity of the weather.

Level 1: Normal operations - no severe weather.

Level 2: Travel with caution - police advise people that conditions for road travel may be hazardous.

Level 3: High risk of disruption for road journeys - police advise that there is a high risk of disruption for road journeys. Travellers are likely to experience significant delays.

Level 4: Avoid travelling on the roads - journeys should be avoided. Severe delays expected.