Saint will be run by David Gamble and Simon Labbett, the digital creative team that joined RKCR/Y&R in April 2000. As well as creative, the agency will also offer communications strategy and digital media planning services.
The company will be run as a standalone profit centre and will work on existing RKCR/Y&R accounts, as well as pitching for new business.
Until now, RKCR/Y&R has offered existing clients a digital capability from within the main agency, but has taken the decision to launch a standalone business to meet increased client demand.
Gamble and Labbett will report directly to James Murphy, the chief executive at RKCR/Y&R, who said: "A lot of clients like the stability of a specialist agency. We looked at a number of options, from acquisitions to partnerships, but thought our own start-up was by far the best idea.
"It also means we can expand our offering. If you can incorporate really good media planning and response planning into the business, you have a much stronger offering."
The duo will be joined by Joseph Heath and Adam Graham, also from RKCR/Y&R. Heath is a digital account planner, while Graham will become the director of production and technology.