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.

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.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.