Mulberry Tree

sally.waters

We have a lovely Mulberry tree - about 24 feet high.  It was becoming a bit overgrown and we had a tree surgeon in who trimmed it back about a month ago.  Now all of the leaves appear to be dying.  The damage to the leaves seems to start out from spots of brown and it almost looks like insect damage rather than something to do with the tree surgery.  I've attached a few photos - can anyone advise?  I'd like to do whatever I can to save the tree.  Many thanks.