The clutch is hydraulic, so you've got a leak somewhere in the system, most likely in the hose that goes from the solid lines at the firewall to the slave cylinder.
You can see the slave cylinder in the picture below - on your car it will be under the top mount and between the two turbos, so I doubt you'll even be able to see it without removing the top mount.
If you're going to attempt changing it yourself, make sure you've got some hydraulic spanners before you start...

Thanks guys.at first I thought it may have been the spring that returns the pedal to its original position but it's def not that.
This happened at 10pm the other night and I haven't had the time to look at it during the day yet.this is my first Suby I've owned although I've owned a fair few other imports.
I was thinking of attempting this myself but I just don't have the space or tools anymore after moving so I'll get it towed to my mechanic and pay out the $$$.really sux thts it's happened over Xmas time and he ain't open for another 2 weeks . Pushbike for me till then

I might have a look at that tomorrow .when it gets to mechanics , it's gettin a new clutch , flywheel and fluid. I'll go all out .