The body plans to meet a variety of agencies over the next few months when its current contract with communications consultancy Portland ends next year.
Portland won the contract from MHP back in 2013, with a brief that focussed on political monitoring and engagement, and strategic comms counsel.
PRWeek understands the pitching process will be procurement-led. A full brief is still being developed, but it is expected to focus on corporate comms and engagement.
The new agency is expected to be appointed in the spring.
A track safety campaign called 'You vs Train' for Network Rail, British Transport Police and the wider rail industry won the Best Use of Planning, Strategy and Evaluation category at this year's PRWeek UK Awards.
It followed 2017's 'Small Talk Saves Lives' campaign for Network Rail, Samaritans, British Transport Police and Rail Delivery Group, which tackled suicides on the railway and was named Campaign of the Year in the 2018 Campaigns for Good Awards.
Both campaigns were from PR agency Pegasus.