The agency, set up by former Borkowski PR director Mark Cooper and former Sputnik director Matt de Leon late last year, has been retained to handle ad hoc work to promote brands such as Baileys, Guinness and Pimms.
The brief does not affect the remit of PR agencies working for Diageo's individual brands. Van will be expected to generate consumer coverage beyond that achieved by Diageo's current agencies.
Van is also charged with raising the profile of Diageo's major brands through surveys about lifestyle trends.
Other work includes promoting the brands around key dates or seasons such as St Patrick's Day, the summer and Christmas.
The agency reports to Diageo GB head of brand PR Clare Fleerackers.
Founder and former chairman of Lexis PR Tim Adams is co-owner of Van and heads the management team as executive chairman.