CHI parted company with the Telegraph in order to work on the £15 million Times Media business, which News International moved from Rainey Kelly Campbell Roalfe/Y&R this week without a pitch.
A Telegraph spokeswoman declined to comment on the logistics of the search, although a source says the company has started drawing up a long-list of agencies.
The Times win reunites CHI with Katie Vanneck, the former Telegraph marketing director who recently rejoined the Times to head up sales and marketing.
As part of the account move, Times Media has also served notice on its digital agency, Joshua. CHI will work in an integrated capacity on the business.
Vanneck said: "CHI & Partners is a media-neutral, fully integrated agency, whose structure and approach mirrors that of our business, offering us a one-stop shop for all of our marketing activity."