Shaun Twomey, of Collins Solicitors in Watford, represents victims of the Southall and Watford train crashes. He told BBC News Online that survivors of the Paddington disaster may have to fight to establish who is liable to pay damages.

"In law you first have to identify the defendant. This is more difficult since privatisation as each train company has its own firm of solicitors and insurers," Mr Twomey explained.

"In the case of the Watford crash we had to issue proceedings before anyone admitted liability. This wouldn't have been the case prior to privatisation, as only British Rail would deal with the claim.

"I have recently spoken to victims of the Watford rail crash who are still sorting out claims.

"Fortunately, after the Southall disaster the insurers took a responsible view, processing claims sensitively and efficiently," he added.

Fire officers search a carriage in the latest tragedy

But Ian Walker of the Association of Personal Injury Lawyers said he anticipated that someone would "concede liability within seven days".

Mr Twomey said he had already received several enquiries about compensation from victims of the Paddington crash.

"Many people want to know if they can make a claim. They don't realise they don't have to have significant physical injuries to make a claim, as the psychological effects [of such a disaster] can be devastating."

Mr Twomey said compensation claims could range from small claims for soft-tissue and orthopaedic injuries to six-figure claims for devastating injuries.

"Some claims will be between �5,000 and �10,000, some will be for millions of pounds," he said.

'Payment within three months'

The solicitor explained that the families of the deceased would be able to make claims under the Fatal Accidents Act, for dependency (loss of financial support), bereavement (a statutory claim of �7,500), and expenses associated with death, such as funeral costs.

He advised claimants to seek specialist advice when making a claim and not to go to their local high street firm.

"It will take time to decide the amount of compensation, as a victim's prognosis - their future care needs - has to be established."

But he added that victims should not have to wait for years to receive money, as once liability had been established interim payments - covering immediate financial and care needs - should be paid within three months.

"In a case where a claim runs into six figures an interim payment of about �10,000 is not unusual," he added.