Celebrity chef Jamie Oliver is to give evidence to MPs amid a row with ministers over a review of sugar tax proposals.
The Health Select Committee is due to hear from Oliver and Public Health England (PHE) chief executive Duncan Selbie as part of its inquiry into efforts to tackle childhood obesity.
The TV star and businessman has been campaigning for a levy on sugary drinks, amassing nearly 150,000 signatures on a petition demanding a Commons debate.
Last week Oliver added his voice to criticism of Jeremy Hunt over his refusal to release a PHE review of evidence on the policy before the publication of a Government strategy on childhood obesity.
He suggested that the Health Secretary was "dithering when faced with a major crisis" rather than taking bold action.
Committee chairman Sarah Wollaston has summoned Mr Selbie to explain why he will not defy Mr Hunt and publish his organisation's evidence review.
After the session Oliver is due to speak at a meeting of the All Party Parliamentary Group for Diabetes.