JAKARTA, Indonesia — A plan by officials in an Indonesian city to ban women from straddling motorbikes has prompted an outcry from critics, who say local leaders are infringing on women’s safety and freedom in the name of religion.

Leaflets have been circulating for a week in Lhokseumawe, in Aceh Province on the island of Sumatra, informing residents about a proposed bylaw that would prohibit women from sitting in a straddle position or holding on to the driver while riding on the back of a motorbike.

Most Indonesians are Muslims, but Aceh is the only province that seeks to strictly enforce Islamic law, or Shariah. The province already has bylaws prohibiting gambling and adultery and restricting how women may dress in public, with penalties that include public canings.

The mayor of Lhokseumawe, Suaidi Yahya, proposed the straddling ban in a New Year’s speech, saying that it was “improper” for women to sit with spread legs and that women should only sit sidesaddle, a practice that opponents say is both less comfortable and less safe.