Former Spanish President José Luis Rodríguez Zapatero has acknowledged involvement in managing the relationship between the bank Santander and the airline Plus Ultra. Details of this interaction are not fully outlined in available information, but it is known that Zapatero recognized some level of management or arrangement with the bank regarding the airline. For more specific details about Zapatero's acknowledgment and the context surrounding his involvement with Plus Ultra, further information can be found through additional sources, including a recent declaration from the former president.