  Repeating X-ray bursts from the Galactic magnetar SGR 1806-20 have been
observed with a period of 398 days. Similarly, periodic X-ray bursts from SGR
1935+2154 with a period of 238 days have also been observed. Here we argue that
these X-ray bursts could be produced by the interaction of a neutron star (NS)
with its planet in a highly elliptical orbit. The periastron of the planet is
very close to the NS, so it would be partially disrupted by the tidal force
every time it passes through the periastron. Major fragments generated in the
process will fall onto the NS under the influence of gravitational
perturbation. The collision of the in-falling fragments with the NS produces
repeating X-ray bursts. The main features of the observed X-ray bursts, such as
their energy, duration, periodicity, and activity window, can all be explained
in our framework.
