Crease Nurb Loop

I’m modeling a tube that looks like this:

Look at the largest scaled loop, you can see that it’s smoothed and round but I want it sharp and creased. I know on edges that are subsurfed you can Ctrl+E the edges but this isn’t working for a nurbs surface like this.

Any advice would be greatly welcome thanks!

Im not sure what it is. A tube? For what? Is it a game model, just to use as practise in modelling?
Just try explain a little better.

Its supposed to be, or eventually will be, a model for a Keyblade in the game Kingdom Hearts. I wanted to do the actual blade modeling with nurbsurfaces because I can control them very efficiently, but arrantly not. Heres the blade I’m trying to emulate:

Don’t know much about NURBS, but I guess that you could add two more `edge loops’ on both sides of the edge which is meant to be sharp (like you can do with catmul clark subdiv).

OK thanks, that puts it into perpective a bit more.