What constitutes a "Clear Runway"

[fireflybob]

In the UK at an aerodrome with NO Air Traffic Control Unit the Rules of the Air does not permit one to land unless the runway is "clear".

Obviously common sense says that if you can see that the runway is clear (and likely to remain so) and there is no other airmanship reason which precludes a safe landing then it is safe to continue and land.

However, if an aircraft (or part of it!) is encroaching on the holding point line is the runway technically "clear"?

Thanks for any input.