"We need to take it in steps and we have got money in the forward programme," said South East Regional Assembly (SERA) director of development Martin Tugwell.
"We can build on the investment in ticketing by South West Trains in Guildford and the Solar travel card in Southampton."
Tugwell rejected claims that the project was unrealistic given the difficulty of persuading so many private transport operators to comply with one scheme.
"The rail operating companies already have compliant ticketing under the terms of their franchise agreements and we want to build on that," he said.
Lobby group A Campaign for Better Transport welcomed the initiative but called for a national scheme."It's great that SERA are doing this but we want to see DfT lead on this and different regions to work together on a national scheme," they said.
The SEEDA plan also includes plans to encourage better links between rail and other transport modes.