Under the new arrangement, COI will have no direct involvement in the DfT's dealings with agencies, but it will view all DfT agency briefs.
This will give it the power to ensure transport campaigns do not clash with other government campaigns.
The move follows talks between COI's chief executive, Alan Bishop, and the DfT (Campaign 10 February). From May, the DfT will be obliged to use COI's roster of agencies. However, Euro RSCG London will continue to handle DfT work, despite not being on the roster.
The DfT will liaise directly with creative agencies and retain charge of pitch decisions after consulting with COI on its choice of agencies.
Under the new arrangement, the DfT's Think! road- safety campaign will continue to be handled by Abbott Mead Vickers BBDO, Leo Burnett and Carat.
The department's £500,000 Transport Direct ads will continue to be handled by Euro RSCG.
Before this agreement with COI was reached, the DfT's roster comprised Euro RSCG, Leo Burnett, Rainey Kelly Campbell Roalfe/Y&R and AMV BBDO.
Government ministers were concerned that this division, which came after a rift between the two bodies in 2002, undermined the COI's ability to achieve optimum media discounts.