Boris Johnson today suspended the London congestion charge for the rest of the day after almost all public transport ground to a halt in the worst snowfall to hit the capital in 18 years.
The entire bus service was withdrawn just after midnight on Sunday night, forcing Londoners to find other means to get to work this morning.
The mayor of London announced his decision to suspend the £8 congestion charge for the day this lunchtime, as only limited bus routes and one tube line were properly running.
It is believed to be the first time that the entire bus service has stopped operating in the capital, according to a spokeswoman for Transport for London, the body responsible for public transport in the capital. London today experienced sub-zero temperatures, with up to eight inches of snow in some areas, and more expected.
By tonight, further snowfalls could leave parts of London under up to a foot of snow.
Johnson, who is also chair of TfL, said he and his officials were doing "everything we can to get the city moving".
Johnson, who travelled from his north London home to City Hall by bicycle earlier today, said: "I especially want to thank those who have worked to get tube services running, clear the roads and, I am proud to say, have now got a limited bus service running. As a gesture of my appreciation for those who have travelled to work this morning I have instructed TfL to suspend the congestion charge today."
The mayor described the weather conditions as the most challenging for London in two decades.
"We have done pretty well in what are extraordinary circumstances," he told the BBC London news programme this lunchtime. "This is the right kind of snow, it's just the wrong kind of quantities. I have never seen anything like it."
Asked why London seemed far less equipped to deal with snow than other cities around the world, Johnson said that the rarity of heavy snowfalls in the British capital did not make it worthwhile to invest taxpayers' money in snowploughs, as cities such as New York do to cope with the more regular snowfalls they experience.
Snowploughs are needed to clear heavy snowfalls from the road because standard gritting does not melt snow.
Johnson's comments were echoed by David Brown, TfL's managing director for surface transport, who said that staff were working flat out to get services running, in pretty "treacherous" conditions, but that, ultimately, the resources needed to deal with extreme and rare weather conditions had to be balanced with other demands on TfL funding.
"We are balancing the level of resources," he told the BBC. "It is about priorities, but we are doing our best to get as many services running as we possibly can."
The mayor also urged Londoners to check on elderly neighbours and others who wer vulnerable in freezing temperatures.
Travellers were left stranded from last night as the capital's 8,000 buses were kept off the roads due to safety fears.
TfL said its staff were out all night with gritters fitted with snowploughs to clear the main roads, called "red routes", which fall under its responsibility.
But London's local councils are responsible for the majority of the roads needed to allow bus services to operate today, including the snow blocking buses' exit from bus garages.
TfL owns just 5% of London's main roads, which routinely carry a third of all London traffic.
The rest of the capital's streets are the responsibility of the 33 boroughs.
A TfL spokesman said: "The vast majority of London's bus services operate along local-authority maintained roads, which have been particularly affected by the heavy snowfall. Local authorities are responsible for 95% of the roads network in London and the unsafe condition of the roads network last night was one of the major factors in TfL's decision to withdraw bus services throughout London on the grounds of safety.
"We're working with the local boroughs to ensure that they can do all they can to clear the roads around bus garages, so we can run services again."
By late morning, a limited bus service had resumed on a small number of bus routes, but more snowfall expected later threatened to disrupt services for the rest of the day.
A spokesman for the umbrella group for London councils insisted that the boroughs were working as hard as they could to clear the roads, with most having started preparations yesterday morning.
The London Councils spokesman said: "It is quite an excessive amount of snow that has come down. TfL roads are used constantly so they do not get a chance to build up as much snow."
The spokesman also pointed out that the transport commissioner, Peter Hendy, had written to all borough chief executives today and acknowledged that councils could not be expected to possess the snowploughs that were needed to clear the roads in light of the exceptional snowfall.
Westminster council said it put its cold-weather operation into action as soon as it realised that severe weather was likely.
Over 100 staff have been gritting main roads and pavements since yesterday morning and worked overnight.
The council has one gritting machine for every square mile of Westminster and by this morning had used 300 tonnes of gritting salt.
Snowploughs are useless in a densely populated area such as Westminster, a spokesman explained, because the snow would be thrown on to the narrow pavements and hamper pedestrians.
"These are extraordinary weather conditions, but we have deployed 120 staff and seven gritting machines to help keep central London moving," he said. "We will continue to work today and through tonight to make life as bearable as we can for those living and working in central London."
The Underground system was also affected by the snow in areas where the trains run above ground, despite de-icing trains running overnight.
Ten of the 11 tube lines on were either completely or partly suspended.
Just under a third of London's train have de-icing equipment.
Signal failures caused by the depth of the snow also hampered tube travellers.