Liberty Global, a European cable operator, and Vodafone, a mobile phone company, have yet to work out how to progress the exchange of assets, months after they announced they were in talks. In a statement on Monday, Liberty’s chairman John Malone said, “Conceptually there could be some real value created but realistically we haven’t been able to figure out a way to do that that’s mutually successful.” He also added, “That doesn’t mean that we won’t find a solution, nor does it imply that we will.” In June, Vondafone announced it was in early talks about exchanging selected assets with Liberty.