The business, previously held by Mediahead, includes planning and buying across several European markets.
Zenith Optimedia's office in Spain was instrumental in winning the account, but its London office will plan and buy a UK campaign set to break in April. The campaign will focus on press and poster activity, including ads in fashion magazines such as The Face, ID, Glamour, Vogue and Esquire.
Pepe has not spent significantly on UK above-the-line advertising in the past year. However, during the 90s the brand established a strong creative history with a series of ads created by Publicis, HHCL & Partners and then Leagas Delaney.
Creative is currently developed in-house, with recent campaigns including a group of denim-clad models reclining on a park bench wrapped in a Union Jack flag.
The account will be run from Zenith Optimedia's Spanish office. Its UK department, village@optimedia, specialises in fashion and beauty brands, such as L'Oreal and Ralph Lauren.
Pepe also has a website called pepejeans.tv that offers information on its latest garments, a shopping channel and general lifestyle information and content.
UK advertising from Pepe will be competing against the higher adspends of brands including Levi Strauss, Lee and Wrangler. Levi's spends around £8 million above the line while Wrangler spends more than £1 million. Other competitors, including Diesel, Guess and Replay, have also developed their presence in the highly competitive and crowded denim market.