The New York-based agency is awaiting the outcome of other IPG-led global pitches, which would further boost a UK hub.
R/GA's founder, Robert Greenberg, said he wants to use London to grow relationships with existing global clients, which include Levi's and Nike, while competing for local business.
"We know about the likes of AKQA, Modem, Agency. com, glue and Dare," Greenberg said. "The market is different and the agencies are smaller, but the potential is huge. We hope to get into healthy competition once we have the capability in place."
Recruitment is underway with a view to growing the London office over the next 18 months. After sharing office space with an IPG sister company, the agency will move into its own premises.