The company has used undisclosed regional agencies for project work in the past, but is now seeking to hire just one agency to cover the bulk of its PR and PA work.
RMC is aiming to boost its 'low-key profile', according to UK comms manager Vicky Leonard, who added that the hired agency will handle B2B and B2C campaigns, targeted at 'everyone from consumers to contractors'.
The contract will involve work across all four RMC divisions in the UK, which are: Aggregates, Building Products, Readymix and Cement.
There will be a strong regional element to the PR work, with Leonard saying that campaigns are likely to involve issues such as 'community work surrounding quarry excavation' and health and safety issues at a national level.
She said RMC is seeking to hire a full-time retained agency as a reflection of the 'need to co-ordinate reputation management across the divisions in the UK'.
She added: 'RMC's profile is low-key at the moment and there are obvious business advantages of raising our profile.'
RMC requested credentials from around 15 agencies and has whittled these down to 'around six or seven'.
Leonard, who is co-ordinating the pitch and to whom the appointed agency will report, said that she expects to invite just 'two or three' agencies to formally pitch for the work.
Leonard added that some of RMC's current agencies are involved in the repitch and, should they not secure the main contract, stand a chance of handling project work in the future.
Leonard joined RMC in a newly created role from a PR manager role at Sainsbury's property arm two months ago.
RMC has seven in-house comms staff who handle investor relations, website development and lobbying work in both Westminster and Brussels.
RMC's international headquarters are in Thorpe, Surrey. However, most of its 8,000-strong UK workforce are employed throughout the country, with a concentration of 700 in the Midlands at sites in Bromsgrove and Rugby.
'We are really starting with a clean sheet to raise our reputation across all of our stakeholders,' added Leonard.