The move will stop short of a merger of Universal and Initiative, with each network maintaining its own brand and P&L. However, Brien is likely to develop areas in which the two networks can collaborate to a greater degree, including new business, digital media and research.
Sources close to IPG said that the changes would result in some streamlining of regional management at the networks. They said that Brien had met with the IPG chief executive, Michael Roth, this week to iron out details.
The move would mark a partial U-turn by IPG, which disbanded its media unit IPG Media a year ago.
IPG Media had brought together Initiative and Universal under the management of Mark Rosenthal, the chief executive of IPG Media, who subsequently left the company following a period of illness.
IPG instead decided to align Initiative more closely with sister creative network its DraftFCB.
In key markets such as the US and the UK, the two networks have continued to work together on media negotiations via the Magna buying unit. However, IPG is said to have recognised that the two brands can work more closely together to give the group more clout in the media world.
In the face of strong competition and a string of high-profile account losses, Initiative and Universal have struggled in recent years to grow at the rate of some of their rivals.
According to Recma, Universal is the eighth-ranked media network in the world, with billings of $12.95bn, while Initiative is ranked 9th in the world, with $11.64bn in billings.