Mrs McCann, whose daughter Madeleine went missing from her family's holiday flat in the Algarve shortly before her fourth birthday, joined other mothers of missing children as she talked about the lack of emotional support available to families.

Calling for the Government to show its support, Mrs McCann said there was 'currently no legislation to protect missing people and their families left behind'.

Kate McCann joined Nicki Durbin, right, and Sarah Godwin to highlight the case of their lost children Madeleine, Luke and Quentin

Speaking outside the Commons while holding up a picture of Madeleine, Mrs McCann said: 'If your house is burgled, you are automatically offered victim support with emotional, practical and legal assistance.

'If your child goes missing, you may get nothing. This parliamentary inquiry has the potential to change that.'

She went on: 'When someone you love goes missing, you are left with unimaginable, unending heartbreak, confusion, guilt and worry.

'In addition to the reassurance that everything possible is being done to find their missing loved one, families need support. And they should be spared the additional pain of financial and legal bureaucracy.'

Madeleine McCann went missing on May 3, 2007

Mrs McCann, 43, issued her appeal to the Government as Scotland Yard continues its review of the investigation into her daughter's disappearance in Praia da Luz on May 3, 2007.

Last month, Mrs McCann, from Rothley, Leicestershire, published a highly-personal book about Madeleine's disappearance in a bid to revive efforts to find her daughter.

The official Portuguese inquiry into the disappearance was formally shelved in July 2008, although private detectives employed by the McCanns have continued the search.

Mrs McCann was joined by Sarah Godwin - whose son, Quentin, was 18 when he went missing in New Zealand while on his way to an after-school job on May 20, 1992 - and Nicki Durbin, whose son, Luke, 19, went missing four years ago.

The three mothers, each holding images of their missing loved ones, faced the press ahead of the first session of the inquiry.

Martin Houghton-Brown, chief executive of Missing People, said: 'From dealing with finances, insurance policies, bank accounts and mortgages through to having a missing person declared presumed dead, families left behind often struggle to deal with institutions that have no system for their clients going missing.

'This inquiry is a landmark opportunity for parliamentarians to ensure that families are able to access the full range of support that they so desperately need.'

Quentin Godwin, left, was 18 when he went missing in May 1992 while Luke Durbin disappeared on May 12, 2006 aged 19
The three mothers, each holding images of their missing loved ones, faced the press ahead of the first session of the inquiry

Mrs McCann told the MPs she did not think it should be left to 'grieving parents' to search for their child.

'I don't think this should be the role of grieving parents,' she said.

Mrs McCann added that this was compounded by a 'lack of communication and information'

Kate McCann: 'If your child goes missing, you may get nothing'

Calling for a single point of contact between the families of missing people and the police, Mrs McCann said: 'To be left in the dark when your child is missing and at risk is unbearable.'

Human beings are not equipped to deal with such ordeals and more support is crucial if 'families are to survive'.

She went on: 'Many people have been worn down by this process because it's absolutely relentless and exhausting.'

But she added that now Scotland Yard was involved, 'I feel the chances of her being found are improving'.

Mrs McCann said that, despite being medically trained, she simply 'could not function' when Madeleine went missing.

'It was the first time in my life when I felt out of control,' she told the MPs.

Counselling had helped 'to talk, to vocalise our fears and to challenge our fears', she said.

Ms Durbin also spoke of her 'terror' at hearing about the discovery of a decapitated body on the local news, fearing it was her son, but not having anyone to call to find out more.

A point of contact with the police was crucial, she said.

Her son went missing after a night out in Ipswich in 1996, she told MPs.