Pruning would have to be very severe in order to clear the pathway. It would be one-sided and ugly, and lose the gracful weeping form, and then regrow with a vengence and be a continual maintenance chore.
If mine, I would re-build the pathway to curve around and allow more space for the tree, and not take a chance of losing it.
Prune from underneath, by removing the lowest branches, and then selectively thin the remainding crown. If you are not sure how to go about this, then best to hire a professional with good references and sample jobs or photos you can see. This kind of pruning is not a skill that all gardeners have, it's challenging even for an experienced arborist. Many will just hack it back and therefore lose the ideal form.
Moving a tree of this size and maturity is really a job for professionals. the soil root ball required will be heavy and needs a two or three man crew to dig and lift it out of the hole and move it and place it in a newly dug hole. It's hard to do it without breaking up the soil, unless you really know what you are doing. And thats in the best of circumstances, and your tree is not.
It is so close to the concrete pathway that it is impossible to dig an adequate size root ball for successful transplanting during the growing season. Therefore moving it during winter dormancy would be best. And at that time you can get away with a smaller root ball and some soil loss.
Is that a UK postal code? If so then you should wait a few months, until November/December. If Australia, it must be fall now, so wait another month or two until fully dormant.
But please seriously consider moving the pathway and not the tree. Don