LONDON (AFP) - Britains most brutal winter in decades caused chaos for travellers Wednesday as snow and ice hit airports and roads, while bitterly cold temperatures cloaked much of Europe. Millions of people in London and the south-east of England woke up to heavy snow after storms spread overnight from Scotland and the north of England, where they have caused problems for days. The current cold weather started in mid-December and it has been the most prolonged spell of freezing conditions across the UK since December 1981, forecasters the Met Office said. Bitterly cold and wintry weather is forecast to continue for the next couple of weeks with further snowfall expected at times. Southern counties could be hit by to 40 centimetres (16 inches) of snow, the Met Office said. Temperatures across much of the rest of Europe are also freezing. Norway, currently dogged by a cold front from Siberia, has been among the coldest, with temperatures in the central town of Roeros falling to -41 degrees Celsius. The wintry conditions have raised concerns about how Britains infrastructure can cope. The countrys biggest salt mine warned it was having to ration supplies because it was simply not possible to meet demand from all the countrys local authorities who are fighting to keep roads gritted and accessible. Transport links in the densely-populated southern and central parts of England were hit hard by the cold weather. Londons Gatwick airport was closed as staff battled to clear snow from the runway, while Luton, Birmingham and Southampton airports are also suffering delays and cancellations. Travellers catching flights from London Heathrow are being warning to check with their airline before travelling to the airport and leave extra time for their journeys. Meanwhile, the military was called in to help the drivers of up to 1,000 cars which were stranded overnight on a major road in Hampshire, southern England. Many commuter train routes into London were also delayed or cancelled, along with those in the north of England. Hundreds of schools around the country are closed and a string of football games have been called off, including Tuesday nights Carling Cup derby between Manchester United and Manchester City. After days of bad weather, attention is now turning to how infrastructure services in Britain are coping. The National Grid issued a gas balancing alert for only the second time ever on Monday after a 30 percent surge in demand because of the weather. This is an indication that it may be necessary to cut supplies or get hold of more in order to avoid what it calls a gas supply emergency. A spokeswoman stressed that supplies were in place to cope with demand. But the main opposition Conservatives have obtained figures which they say shows Britain has only eight days of supplies in storage, based on current usage levels. When will the government understand we need more storage capacity and the ability to get gas to consumers so nobody has to face the possibility of going without gas during cold snaps like this one? Meanwhile, the operators of Britains biggest rock salt mine, Winsford in Cheshire, northwest England, said it was facing unprecedented demand. We would obviously like to be able to fulfil every authoritys needs in full but the reality of the situation at present is that that is simply not possible, the Winsford Salt Union said. We are, therefore, working closely with customers and with government agencies to try to prioritise deliveries according to local needs.