You need to squeeze the line at two points with your fingers and pull, but really there is no need to remove it if you have removed it from fuel tank, Swivel it down and you can leave it on to remove the intake and t/b unit it will be fine.
Pull the fuel pump fuse then start the bike and let it die from lack of fuel. The bike will only run for a second or two. This will safely remove the pressure from the fuel system. Then you can safely remove the fuel line from the tank. Lift up on the collar on the fuel inlet line to the tank and pull the hose down the same way you would as a air hose coupling.