The campaign, to be handled by Blue Rubicon, is understood to be worth an estimated six-figure sum, will seek to "debunk myths" about the quality of McDonald's employees and employment practices. The 'McJob' tag comes from Douglas Coupland's 1991 novel 'Generation X'.
The launch follows the news that McDonald's is considering applying for the Department of Health's "5 a day" nutrition logo after deciding to sell fruit in its UK restaurants for the first time.
The launch comes as the fast-food giant is under fire around the world from pressure groups that see it as partly responsible for fuelling an obesity epidemic among young people.
McDonald's hopes it can use the logo on Happy Meal packs that include a portion of fruit instead of fries. The government has yet to start approving commercial use of the logo, which will only be used to promote fruit and vegetable products without any added fats, sugar or salt.
McDonald's decision to sell fruit is part of a menu revamp, which the firm said is "designed to improve customer choice".
The PR employment practices and pay campaign will seek to draw attention to the fact that new staff can rise to management positions in as little as 18 months.
To illustrate this, McDonald's will promote the fact that more than two-thirds of McDonald's restaurant managers started as hourly paid staff members and almost a fifth of McDonald's franchisees -- now running on-average £2m a year businesses -- were also once hourly paid employees.
According to PR Week, Blue Rubicon managing director Fraser Hardie, who will lead a team of five reporting to McDonald's head of corporate affairs Nick Hindle, said the campaign aims to redefine the way McDonald's is seen as an employer among opinion formers.
Separately, it has emerged that McDonald's will not be renewing its controversial sponsorship of children's ITV programming strand 'Diggit', which started last year.
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