Also because of a government billing, local authorities now have the power to control what the owner of the tree can do if it really is restricting your light. They first issue a "remedial notice," which orders them to lower the height of the tree. If the owners do not listen, they could get a fine up to £1,000.
Basically, you can't do anything about the blocking of light. Only if it actually crosses the property line. While an individual has some ability to control what happens over their property, there are limits. It would be pretty ugly if every airplane flight had to clear its flight path with every property owner it was going to cross over!
Aggie80