By constantly monitoring at least one complete hemisphere of the sky, neutrino telescopes are
well designed to detect neutrinos emitted by transient astrophysical events. Real-time searches for
ANTARES neutrino candidates coincident with gamma-ray bursts, High-Energy Starting Events
and Extremely High-Energy Events detected by IceCube and gravitational wave (GW) candidates
observed by LIGO/Virgo are performed. By requiring coincident detection, this approach increases
the sensitivity of the telescope and the significance of a potential discovery. The latest
results of these analyses will be presented. In particular, a neutrino follow-up is performed after
the detection of GW events by the LIGO/Virgo collaboration. Because of the good angular
accuracy of neutrino telescopes compared to current GW detectors with two interferometers, a coincident
detection would drastically constrain the position of the GW source on the sky, bringing
valuable information for subsequent electromagnetic follow-ups. Since no coincident ANTARES
event has been detected so far, the neutrino fluence and the total energy emitted in neutrinos are
constrained for each GW alert.