The restructure saw Reed replace Robin Lauffer, who took on the new role of group executive planning director. Lauffer now heads the McCann subsidiary Magic Hat.
Tamara Ingram, the chairman and chief executive at McCann-Erickson UK and Ireland, said: "Pascale did a fantastic job. She helped the agency refocus on planning and creative, and we're going to continue to do that.
The agency has gone from strength to strength in the last seven years due to the continued improvement of our product and she was part of the team that did that."
A replacement for Reed has yet to be made, although it is understood the agency has started talks with prospective candidates about the UK role. Ingram said: "We'll be looking at heads of department as well as an executive planning director."
The agency made efforts to bolster its planning department recently by hiring the former Circus chairman and founding partner, Paul Twivy, as its chief strategic planning officer for Europe, the Middle East and Africa.
Twivy's appointment filled the vacancy left by the departure of the former chief strategic officer, Lee Daley, the previous July. Daley left to become the chief executive of WPP's Red Cell network.