Interpublic Group of Companies has announced the immediate departure and replacement of McCann Worldgroup's British CEO Nick Brien, with native New Yorker Harris Diamond, CEO of another Interpublic division, the Constituency Management Group, named as his successor.

The pressure has grown on Brien throughout his two years at the helm of McCann, who has presided over dwindling revenues and the loss of clients including NescafĂ©, Exxon Mobil , Hewlett-Packard and Lufthansa. The Wall Street Journal claimed Interpublic were considering replacing him, as did Advertising Age; quoting "insiders", the publication suggested that it would be surprising if Mr. Brien "wasn’t gone by the start of 2013."

Interpublic CEO Michael Roth said in a statement that Harris Diamond: "understands the business needs of global CEOs, across a range of industries. He has a proven track record of effectively managing a portfolio of agencies and growing the top line. He has created a strong culture of collaboration, which is increasingly key in a marketing landscape that requires integration of services. And he brings a deep knowledge of McCann in light of the alignment between Worldgroup and a number of the agencies within CMG, such as Weber Shandwick and FutureBrand."

There was little condolence for the ousted Brien.

"We thank Nick for his commitment and for driving change at McCann during his tenure."