It is understood that Lexington, headed by founding partners Mike Craven and Ian Kennedy, emerged triumphant from a three-way pitch to land a 12-month contract. Kraft had not previously retained a PA adviser in the UK.
Kraft Foods UK head of corporate affairs Jonathan Horrell confirmed Lexington's appointment.
The maker of household brands including Dairylea, Philadelphia, Toblerone and Kenco has been something of a food industry trailblazer in slashing the salt content across its product portfolio. But it wants to discourage the Government from implementing a 'traffic light' labelling system, which it argues would demonise entire food groups such as its cheeses.
And while the firm has moved to end advertising to young children, it opposes proposals to implement a ban on food advertising during family-viewing programmes.
It is understood Lexington will be expected to provide strategic advice on these issues and The School Food Trust, a body created to get the food industry and nutritionists to encourage local authorities, schools and parents to improve the standard of school meals.
Kraft runs an initiative based in Gloucestershire to promote healthy diet and exercise to schoolchildren, called Health 4 Schools.