Daniel Brumberg argued that it was in response to the dispute between president Ali Khamenei and popular prime Minister Mir-Hossein Mousavi, that the IRP was dissolved - the Islamic Republican Party served "as a stronghold of radical activism," supporting Mousavi. However, another report states that it was dissolved in May 1987 due to internal conflicts. And the party was disbanded upon joint proposal of Rafsanjani and then party leader Khameini on 2 May 1987 when their proposal was endorsed by Ayatollah Khomeini.