An Indonesian city plans to slap its gay and transgendered residents with a one million rupiah ($70) fine for disturbing "public order", underscoring a marked rise in discrimination against the Muslim-majority nation's small LGBT community.

The country of 260 million is in the grips of a moral panic, with critics saying the vulnerable LGBT minority is being used as a political punching bag in the run-up to 2019 elections.

Homosexuality is not illegal in Indonesia -- except in Islamic law-abiding Aceh province -- but there has been a backlash against the community in recent years.

The shift, led by increasingly powerful religious hardliners, has dented Indonesia's reputation for moderate Islam.

This week, Pariaman city on Sumatra island passed a sweeping regulation banning "acts that are considered LGBT".

The regulation, which has been reviewed by AFP, forbids "immoral acts" between same-sex couples and prohibits residents from "acting as a transvestite", but it offers few concrete examples of banned behaviour.

"Same-sex LGBT and transgender people will be subject to sanctions and fines if they disturb the public order," said Fitri Nora, head of the local legislature.

Pariaman's deputy mayor Mardison Mahyudin said the new rules were born out of "anxiety" about Indonesia's LGBT community.

Anti-LGBT demonstrations have erupted in several cities recently, including the capital Jakarta, while authorities hosed down a group of transgender women in what they called a "mandatory bath".

Several cities in West Sumatra province, including Pariaman, have taken steps to marginalise LGBT groups, and the provincial government called a special meeting Thursday to discuss the issue.

Following the meeting, governor Irwan Prayitno said officials and concerned parties were searching for a province-wide solution to the "LGBT problem".

"At a minimum, we're trying to prevent the population from increasing," Prayitno told AFP.