Layered 5d transition iridium oxides have attracted huge interest due to unconventional Mott insulating states induced by strong spin-orbit coupling and the possible proximity with the physics of high-temperature superconductivity in cuprates. Among all the iridates studied, Sr2IrO4 has been the most extensively investigated. Recently, a global symmetry breaking in Sr2IrO4 has been reported using spatially resolved optical second harmonic generation measurements as well as forbidden Bragg peaks were observed in neutron diffraction. This broken symmetry cannot be explained by neither structural distortions nor by the antiferromagnetic spin order. Instead, it is argued to be caused by a loop-current order similar to the one observed in superconducting cuprates. Therefore we here propose to evidence the existence of the loop current phase using polarised neutron scattering. We consider that D7 with polarization analysis is the most relevant to achieve our goal and request 14 days of beam time.