A system is provided for transferring fluids such as liquefied natural gas between a floating transport vessel and a floating storage vessel utilizing a transfer vessel to deploy, operate and return a fluid conduit to the storage vessel. The fluid is transferred through at least one submerged-subsea catenary flexible conduit, at least one floating flexible conduit, or any combination thereof. A transfer vessel, including a releasable mooring system, is provided for deploying the conduit from the storage vessel to the transport vessel, mooring with a transport vessel, maintaining a unified connection during fluid transfer, releasing the mooring once fluid transfer is completed, returning to and parking on the storage vessel, and storing the conduit between fluid transfers. The transfer vessel and releasable mooring system allows safe, controlled operation and fluid transfer in open sea conditions