In this paper, we prove a sufficient condition that every nonempty closed convex bounded pair
M
,
N
in a reflexive Banach space
B
satisfying Opial’s condition has proximal normal structure. We analyze the relatively nonexpansive self-mapping
T
on
M
∪
N
satisfying
T
M
⊆
M
and
T
N
⊆
N
, to show that Ishikawa’s and Halpern’s iteration converges to the best proximity point. Also, we prove that under relatively isometry self-mapping
T
on
M
∪
N
satisfying
T
N
⊆
N
and
T
M
⊆
M
, Ishikawa’s iteration converges to the best proximity point in the collection of all Chebyshev centers of
N
relative to
M
. Some illustrative examples are provided to support our results.