Airbus gave no date for a further decision, saying there were no front-runners and it wouldn't be rushed into a choice.
"We will decide when we are ready," Chief Executive Tom Enders said in a statement.
"Announcements will only be made when the Airbus and EADS management have arrived - together with the potential partners - at concrete terms and conditions for a promising long-term partnership," Airbus said.
The companies that are eventually selected will become long-term partners of Airbus and share the risk of its planned A350 XWB wide-bodied aircraft, which is planned to enter commercial service in 2013.
Airbus is looking for partners for its manufacturing sites in Filton in Britain, Meaulte and St. Nazaire Ville in France, and Nordenham and Varel in Germany as part of a broad restructuring and cost-cutting program.
Airbus said its parent company, European Aeronautic Defence & Space Co., "is close to making a decision about the incorporation of its Augsburg, Germany site into the process." That decision is expected soon, the statement said.
The bidding process was announced in February and officially launched in May.
Under the A350 XWB program, the partners would share investment and risks but also the benefits from their participation in the program. Partners would manage, invest and further develop the sites and ensure their participation in the current Airbus programs, new participation in the A350 XWB program and the potential participation in future program.