The incumbent is Havas Worldwide London, which will cease working with the company in March. The agency landed the account in 2013 after beating DDB in a pitch.
The review is being handled by Hamilton Associates, which has compiled a shortlist of agencies.
Iglo said the move will not affect its relationship with Havas Media. The agency picked up the consolidated European media planning and buying business in 2014 after a review process.
Carat was the incumbent in the UK, Austria, Italy and Russia. OMD oversaw media in Turkey.
Earlier this year, Birds Eye appointed Recipe to lead its social and digital account in the UK. The agency’s remit includes content creation and digital campaigns.
Andy Weston-Webb, the chief commercial officer at Iglo, said: "As a company, we have recently re-evaluated our business and brand strategy, so this is a natural time to review our needs going forward and the agencies who support us.
"These decisions are never easy and we’re grateful to Havas for the large volume of work delivered last year – their efforts have been highly appreciated."