Over-the-counter payments were taken at newsagents and petrol stations using existing Pay Point machines - also used to pay council tax and rent.

Payment by text messaging, over the internet and by machines in central London car parks also began.

Congestion charging, which will see motorists pay a £5 fee to drive into central London, is being introduced on 17 February.

There have been no customers at all in querying the charge whatsoever. Jay Rasul

But at the last count only around 3,000 households had registered at all.

Transport for London (TfL) is hoping registration will now begin in earnest and said business had been "quite brisk" on Monday.

But at the Costcutter in Spitalfields, east London, two hours went by without any customers asking about the congestion charge.

Some said it was too early to pay, some planned to drive in earlier and others were anticipating a mass non-payment, describing the charge as the new Poll Tax.

Shopkeeper Jay Rasul said there was some confusion about the charge.

Confusion

He said: "As a distributor, I have not been completely informed about the congestion charge.

"There have been no customers at all in querying the charge whatsoever."

Some motorists may be hoping for a last-minute reprieve in the High Court.

Solicitors Class Law believe they have a case under the Human Rights Act for having the charge declared unlawful, if they can prove the consultation process was flawed.

Congestion costs London £4m a week

Partner Stephen Alexander said for some low-paid workers there was no alternative to driving in and so the charge was like a tax.

"Every other tax we have in this country recognises the ability of the taxpayer to pay - this one does not," he said.

Public service unions have also asked the mayor to delay the charge to assess the impact on public services.

Alice Dawnay, UNISON's London nursing officer, said the charge was likely to cost their average member £1,200 a year and fears resignations will follow.

But TfL is confident the charge will be introduced on 17 February as scheduled.

A previous High Court challenge brought by Westminster Council, which claimed there had not been a full and efficient consultation, was thrown out last July.