In late July 2006, the Russian Space Agency and the European Space Agency agreed to collaborate on a different project to develop a new spacecraft. They decided to fund a study under a program labelled Crew Space Transportation System (CSTS) which started in September 2006 and evaluate a capsule type concept, derived from Soyuz. While this program is the follow-on project of the RSA's and ESA's collaboration on a new space vehicle, this program is no longer connected to Energia's winged Kliper design.