  Let $K\subset \mathbb{R}^n$ be a convex body, $n\geq 3$. We say that $K$
satisfies the \textit{Barker-Larman condition} if there exists a ball $B\subset
\text{int} K$ such that for every suppor\-ting hyperplane $\Pi$ of $B$, the
section $\Pi \cap K$ is a centrally symmetric set. On the other hand, we say
that $K$ satisfies the \textit{Montejano condition} if there exists a ball
$B\subset \text{int} K$ such that for every suppor\-ting hyperplane $\Pi$ of
$B$, the section $\Pi \cap K$ is a body of constant width. In this work we
prove the following results where, in both cases, $K$ is an $O$-symmetric
convex body and $B\subset \text{int} K$ is a ball such that $O\notin B$: 1) If
$K$ is strictly convex body and satisfies the Barker-Larman condition with
respect to $B$, then $K$ is an ellipsoid; 2) If $K$ satisfies the Montejano
condition relative to $B$, then $K$ is a ball.
