  We investigate whether inflation in the early universe can be induced by an
extra component of a five-dimensional ${\rm U(1)}$ gauge field in the
Randall-Sundrum warped spacetime or not. We show that an effective potential
obtained by quantum corrections can act as an inflaton potential by finding
parameter regions consistent with Planck 2018 results. In our model, fields
involved in inflation obey a different type of boundary condition from that of
the visible particles, and a surviving Wilson line phase can play a specific
role for physics beyond the standard model.
