Fresh snow forecasts threatened to prolong chaos caused by cold weather as airline and international train services limped back towards normal in parts of Europe on Wednesday.
Disruptions to flights and high-speed train travel in continental Europe and Britain, have created travel chaos for tens of thousands of travellers in the busy Christmas period following heavy weekend snowfalls.
Cold weather was likely to dent fourth quarter growth in Germany, Europe's biggest economy, Volker Treier, chief economist at Germany's DIHK chamber of industry and commerce said.
"A lot of construction projects have been stopped and a lot of business trips cancelled," he said. "Freight transport has also had weather problems. The bottom line is the harsh weather will cost about a half a point of growth this quarter."
German railways put on more trains to help stranded air travellers reach their destinations but in France the national aviation authority asked airlines to reduce services as a precaution after more snow was forecast.
In Britain, the bad weather has caused severe delays to rail services across northern and central districts and forecasters said more heavy snow was on the way.
Travel havoc has triggered calls for legislation to force airports to deal more effectively with bad weather.
European Union transport chief Siim Kallas said he was considering forcing airports to provide a minimum level of infrastructure support during severe weather.
London's Heathrow and Frankfurt airports said on their websites that operations were returning to normal after severe disruptions.
Wolfgang Prock-Schauer, chief executive of Lufthansa's bmi airline, accused Spanish-owned BAA of being unprepared for the heavy snow at Heathrow.
"What is really incredible is that 10 cm (4 ins) of snow closed the airport down for two days and then it operated at one-third capacity," he told the Times newspaper. "BAA was not prepared. It did not have enough de-icing fluid."
A BAA spokesman denied there had been a de-icer issue at Heathrow and said lessons would be learnt but blamed the problems on "unprecedented weather which closed most of northern Europe's airports."
BAA's chief executive Colin Matthews said he would forego his 2010 bonus following the travel chaos, a move demanded by one union representing airport workers.
"My focus is on getting people moving and rebuilding confidence in Heathrow," Matthews said.
Heathrow was scheduled to operate 70 percent of a normal day's service, about 800 flights, but it was still advising passengers not to go to Heathrow unless they had confirmed flights, the spokesman said.
"We're hoping by the end of the day we'll be up to full operation," he said.
British Airways said that, in line with a directive from BAA, it would operate only a third of its normal flights at Heathrow until 6 am on Thursday.
Frankfurt airport was open and running at full capacity, said an airport spokesman, adding there was a backlog of about 3,500 stranded passengers, including some 600 who spent the night on emergency cots at the airport.
German rail operator Deutsche Bahn said it would add extra trains from Wednesday until December 31 to cope with a surge in demand due to air travel disruptions.
Traffic had been starting to return to normal at Paris airports, where some 3,000 people have been stranded.
But the French aviation authority asked airlines to cut services by 15 percent later on Wednesday and 25 percent on Thursday at the country's busiest airport, Paris Charles de Gaulle.
Eurostar, operator of high-speed trains between London and Brussels and Paris, said it would resume normal check-in service, but asked passengers not to show up until an hour before departure "to avoid congestion and an unnecessary wait."
On Tuesday, thousands were forced to queue in the cold for hours around London's St. Pancras station as all Eurostar's seats were taken by travellers bounced from airlines.
Although the logjam of travellers was starting to ease, many passengers were irate.
"This was our holiday of a lifetime," a man at Heathrow who'd been planning to travel with his wife told Sky News. "And it's a nightmare."