Iran on Tuesday announced a list of mostly conservative or hard-line candidates for next month’s presidential election, after several moderate politicians were barred from running. Iran’s Guardian Council, which approves aspirants to elected office, narrowed the field to seven candidates from hundreds who had registered and disqualified prominent figures associated with centrist or reform-minded political factions. The seven candidates — all middle-aged men — are vying to replace President Hassan Rouhani, a centrist who is prevented by term limits from running again.

The council’s selections, which reflect the preferences of Iran’s supreme leader, Ayatollah Ali Khamenei, virtually guarantee the election of a hard-line government at a moment when Tehran is trying to revive a tattered nuclear deal with six world powers, roll back U.S.-imposed economic sanctions and mend relations with neighbors such as Saudi Arabia.

One of the candidates, Ebrahim Raisi, a conservative cleric who heads Iran’s judiciary, is widely viewed as the front-runner and the consensus choice of Iran’s hard-line factions. Raisi, who unsuccessfully ran for president four years ago, is also seen as a possible successor to Khamenei. He has been linked by human rights groups to mass killings of dissidents in 1988, when he served on a panel involved in sentencing prisoners to death.

Two people who were barred from the election were regarded as among a few figures with the stature to challenge Raisi: Ali Larijani, a center-right former parliament speaker and nuclear negotiator, and Eshaq Jahangiri, a reformist and Rouhani’s vice president.

Jahangiri said in a statement that he views “the disqualification of many worthy people as a serious threat to public participation and fair competition of different political parties and movements, especially the reformists.”

Sadegh Larijani, a cleric who serves on the Guardian Council and is a brother of Ali Larijani, issued a sweeping condemnation of the council’s selections. He has defended the body for 20 years, he wrote on Twitter, “but I have never found the decisions of the council so indefensible.”