  Classical electrodynamics is a local theory describing local interactions
between charges and electromagnetic fields and therefore one would not expect
that this theory could predict nonlocal effects. But this perception implicitly
assumes that the electromagnetic configurations lie in simply connected
regions. In this paper we consider an electromagnetic configuration lying in a
non-simply connected region, which consists of a charged particle encircling an
infinitely-long solenoid enclosing a uniform magnetic flux, and show that the
electromagnetic angular momentum of this configuration describes a nonlocal
interaction between the encircling charge outside the solenoid and the magnetic
flux confined inside the solenoid. We argue that the nonlocality of this
interaction is of topological nature by showing that the electromagnetic
angular momentum of the configuration is proportional to a winding number. The
magnitude of this electromagnetic angular momentum may be interpreted as the
classical counterpart of the Aharonov-Bohm phase.
