Steve Gatfield, Burnett's worldwide chief executive, explained that he was proud of the agency's creative output but that this did not deflect from his frustration over its recent failure to generate sufficient new business.
Burnett was recently shortlisted for pitches including the Army, Lloyds TSB and Lego but progressed no further.
The agency has suffered in the economic downturn; its billings fell by 15.14 per cent to £100.19 million, according to AC Nielsen MMS data.
Gatfield said that Haines' appointment will see Burnett expand its non-advertising interests.
"What we are doing is creating a group of high-quality companies under the Leo Burnett banner and Bruce will be overseeing this, whether it be in start-ups or company acquisitions," he explained.
Gatfield identified design and strategic consulting as areas where he is keen to develop Burnett's capabilities further and said that Haines would bolster the existing group companies.
Haines left his job as the chairman of Leagas Delaney at the end of last year, ending a 15-year partnership with Tim Delaney. He is currently halfway through his presidency of the IPA.
Haines, who starts at Burnett on 2 April, said he had been approached by a number of agencies since he left Leagas Delaney but had decided to accept the Burnett offer because of the quality and commitment of the Chicago management team.
"When I left my last place I laid down the criteria that I would only work with quality people who are decent and honest and committed to the business. From the outside I've been impressed with the strides Burnett has made with the creative product and it has done some great work in difficult sectors, which is to be
applauded," he said.
He added his priority was to increase co-operation between Burnett group companies, which include Leonardo and Spring, and to convert more new business into wins.
Whyte, who succeeded Nick Brien a year ago when Brien left to become the president of US corporate business development for Starcom MediaVest Group, has no job to go to.
Whyte's departure follows that of Gerard Stamp, who quit as Leo Burnett UK's chairman two weeks ago.
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