I had this issue on my last Fiesta, couple of years ago I was at the lights on the A406 - went into first gear and the clutch pedal just went - no tension at all. Stuck at the lights, cars beeping, had to push it to the side and call RAC.

Turned out the RAC guy knew exactly the problem and fixed it as he always does, putting a clip on the end of the clutch rod, stopping it falling out the ring. Was perfect since then, but even he said he's done loads of these clips to Fiestas (was an 02 reg)

I'm getting an ST 05 reg on Saturday, definetely checking it out for the clip.