A Baha'i advocacy group has expressed concerns over the fate of minority Baha'is at the hands of Yemen's Houthi rebels ahead of the appeals hearing for one of the community leaders sentenced to death.

The Baha'i International Community said in a statement Friday that the hearing for Hamed bin Haydara, detained in 2013 and sentenced to death last year on espionage and apostasy charges, is due on Tuesday.

The statement quotes Bani Dugal, the Baha'i community representative at the United Nations, as saying the prosecution hasn't addressed Haydara's appeal but is instead making "absurd, wide-ranging accusations."

International rights groups have decried the prosecution of Yemeni Baha'is by the Iran-backed Houthis.

Iran has banned the Baha'i religion, which was founded in 1844 by a Persian nobleman considered a prophet by followers.