The carrier, which is a subsidiary of Air France, is reviewing the account through Creativebrief.
Euro RSCG currently handles the business, having been appointed in March 2009 after a shoot-out against Grey London.
The majority of the account will be focused in the UK but will include some European markets. The appointed agency will be responsible for ramping up CityJet's advertising activity over the next year as the airline looks to focus on highlighting its position as the largest carrier from London City Airport.
Euro RSCG created CityJet's recent £1 million marketing push, which was the biggest since it took over the Belgian carrier VLM Airlines in 2009.
The campaign aimed to reposition CityJet as a "premium but friendly" airline.