Lawmakers in Indonesia's Aceh will vote Friday on whether to make gay sex punishable by 100 lashes of the cane, the latest proposed Islamic regulation in the conservative province that has outraged rights activists.

Aceh, the only part of the world's most populous Muslim-majority nation that is allowed to implement Islamic sharia law, already carries out public canings on people caught gambling and drinking alcohol.

The new draft bylaw, which has strong support in the local parliament and will be put to a vote on Friday evening, explicitly outlaws anal sex between men and "the rubbing of body parts between women for stimulation".

Chika Noya, an independent activist for lesbian, gay, bisexual and transgender (LGBT) people, said that the law was a "big step back" for LGBT rights in Indonesia.

"It's as if we're going back hundreds of years," Noya said.

"The Indonesian government is hypocritical if it lets the bylaw pass. They say they are democratic, they have ratified so many human rights instruments -- why should they allow Aceh to violate basic human rights?"

Gay sex is not illegal in the rest of the country, which mainly follows a criminal code from the Netherlands, Indonesia's former colonial master.

The new Islamic bylaw, which has several articles outlawing different things, will also be the first in Aceh -- on the western island of Sumatra -- to be applied to non-Muslims, both Indonesians and foreigners.

The new bill also proposes 100 lashes for adultery, and reiterates that fraternising between unmarried men and women, and displays of affection outside of marriage, are punishable by caning.

Canings -- which are carried out with thin rattan sticks in public and are aimed at humiliating, rather than causing physical pain -- can be substituted with payments of pure gold or jail time.

The bylaw must also be approved by the home affairs ministry in Jakarta, which indicated last week it may overturn the law on rights concerns.

But Ramli Sulaiman, a local lawmaker who heads the commission that drafted the bill, said all relevant agencies in Jakarta had given it the green light.

Sulaiman, from the Aceh Party, which dominates politics in the province, was confident the bill had strong support in the local parliament.

He admitted, however, punishments for homosexual sex and adultery would be hard to carry out as they both require four eye witnesses to prove the acts took place.

Aceh province is known as the "veranda of Mecca" and has been slowly implementing sharia law since 2001, when it gained a degree of autonomy in a deal with Jakarta aimed at quelling a decades-long separatist movement.