TEHRAN, Iran (AP) — A reformist candidate has dropped out of Iran's presidential election to back President Hassan Rouhani in a widely expected move that will strengthen the incumbent's campaign against a hard-liner.

The state-run IRNA news agency says Eshaq Jahangiri, senior vice president under Rouhani, dropped out on Tuesday, meaning just four candidates remain in the race. The election will be held Friday.

On Monday, Tehran Mayor Mohammad Bagher Qalibaf dropped out of the election to back hard-liner Ebrahim Raisi, believed to be a favorite of Supreme Leader Ayatollah Ali Khamenei.

The election is largely viewed as a referendum on the nuclear deal struck with world powers and shepherded by Rouhani's administration. Iran agreed to limit its enrichment of uranium in exchange for the lifting of some economic sanctions.