It has awarded APCO a newly created two-year contract to provide advice in London and Brussels.
APCO UK managing director Simon Miller said that to help secure new franchises it needed to promote Arriva’s credentials in the areas of safety, reliability, punctuality, ticketing technology and station cleanliness.
He added that as well as winning round the Department of Transport and Strategic Rail Authority, its challenge was to build goodwill among local authorities, local media, and environmental and rail user groups.
Arriva currently operates the franchise to run trains across Wales and the English borders. It is one of the largest bus operators in the UK along with Stagecoach and First Group.
The company’s expansion into Europe, an area avoided by its UK competitors, last month saw it raise its stake in German rail firm Regentalbahn, which runs services in Bavaria and Saxony, by 13 per cent.
APCO won the business after pitching against Weber Shandwick Public Affairs, Fleishman-Hillard Public Affairs (previously known as GPC International) and mainland European consultancies Cabinet Stewart, EPPA and EU Top.