As No Go Britain examines transport access for the disabled, Sir Philip Craven from the International Paralympic Committee says progress is "tremendous" but concedes full equality might never happen.

Full transport access for disabled 'not ever possible'. (Getty)

Sir Philip, president of the International Paralympic Committee (IPC), told Channel 4 News "accessibility for all is good for everybody" and praised the efforts of transport operators.

He said: ""I think there's been tremendous progress made... and there's going to be more progress made."

But he hit out at "unrealistic" expectations ahead of the Olympics and Paralympics.

It is estimated as many as 23,000 mobility-impaired sports fans will be travelling into London on the busiest day of the games, which organisers have vowed will be the "most accessible ever".

So far 175 underground stations have been "improved" and virtually all London buses can be lowered to allow wheelchair access.

If any person with an impairment expects to be able to go everywhere in this country that someone with two legs can do, then I don't think that's ever going to be possible. Sir Philip Craven

Sir Philip is sceptical about those asking for further guarantees.

"Someone who demands by 2012 that every underground station - some of which were built 150 years ago - is accessible in the seven year period between the granting of the games and the games taking place, I think that's a little bit unfair," he said.

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Sir Philip was speaking at a new exhibition at the Science Museum which demonstrates some of the technology behind Paralympic sport.

His comments follow the launch of No Go Britain, a Channel 4 News investigation into the state of public transport for mobility-impaired, visually-impaired and deaf people.

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Britain's most successful Paralympian of all time, Tanni Grey-Thompson, recently told us how she had to crawl from a mainline train because no-one came to help her at the end of a journey, despite her booking assistance in advance. Many similar stories have since come to light.

"Highlighting where, say, Tanni had a problem is probably going to accelerate things and get things right," Sir Philip told us.

"But no-one's perfect.

"And I think if any person with an impairment expects to be able to go everywhere in this country that someone with two legs can do, then I don't think that's ever going to be possible.

"I think we need to be realistic and I'm very pleased with the progress that's been made so far."

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