Your description of the events is too vague and actually contradicts your own story, as others have pointed out.
the van was in the right hand side of the lane behind me. As I was going to turn left I indicated left and pulled up to the left of the van.
He can't start behind you and then you pull up next to him. This won't help your case at all.
Correct me if I'm wrong but the actual events are something more like this:
- You were following a van down Whinney Lane, approaching the junction with A6119.
- Just prior to arriving at the main junction, the van positioned himself to the right-hand side of the lane and stopped.
- The van had positioned himself as if he may intend to turn right down a small lane (Yew Tree Drive), or possibly to cross the A6119 and continue down Whinney Lane.
- The van was not indicating, but had stopped approximately 10 feet before the main junction.
- As there was sufficient room to pass the van on his left hand side, you began indicating left, moved past him on his left-hand side and positioned yourself ready to turn left onto the A6119.
- You were now positioned slightly in front of the van, who was still stationary in the right-hand side of the lane, about 10 feet back from the junction.
- Without any indication the van then made a sudden movement to his left, hitting the driver's door on your car, while you were still stationary at the junction.
Something like that above would at least have made the situation a bit clearer. Whether it would help them to rule in your favour or not, I'm not sure. Without witnesses it will likely be your word against his, and if his story is slightly different, then it'll almost certainly go 50/50.