The managed business travel industry is in danger of sliding backwards unless it develops a self service tool that includes all types of transportation, Tony Berry, HRG's director of distribution services, said.
He said the industry itself had created barriers to entry on the GDSs to hotels, rail, taxis and car companies.
He said companies like taxi companies could not afford to pay GDSs fee, which was a "huge barrier" for them.
"If we do not solve this issue and get all these transportation types into a single source, the industry is in danger going backwards," Mr Berry said.
He added later: "HRG and other TMCs are absolutely committed to raising these barriers to entry to all suppliers.
"It is a key issue. It is difficult to see how self booking tools can progress unless you get more transportation choices on them."
Mr Berry was speaking at a Travel and Expense Management Forum in London organised by Management Solutions (UK).
Earlier Peter Dennis, director of e-commerce development at BSI, a hotel booking agency, said while hotel content in the US on the GDSs was fine, Europe and the Middle East were more fragmented markets.
"It can cost £30 for a GDS transaction so the manager of the Red Lion is going to say 'Forget it. Ring me,'" Mr Dennis said.
He said GDS have been the de facto standard for distribution but web sites worked differently.
He said a one stop portal was needed which would enable booking agencies to work more closely with TMCs buy anyone looking to the industry to adopt one standard would be in for a long wait.
* At the conference Dev Anand, founder of BedFare and MeetingFare and now managing partner of Impetus Marketing, said he thought restaurant spending could be the next area where travel managers sought to control spend. He said he was the UK agent for a website called www.opentable.com which was set up in the US by industry innovator Barry Diller, ceo of IAC, as a booking reservation service for restaurants which also provided MI on a corporate's spend. Mr Anand said the UK branch had now signed up 180 restaurants in Britain, mainly in London.
* see BTE's recruitment site www.businesstraveljobs.com