SINGAPORE unveiled details of its speakers' corner Thursday -- placing a raft of restrictions on use of the open air forum which is supposedly based on London's famous free-speech haven of Hyde Park.

Speeches of a religious nature are banned, as are speeches which "have the potential to cause feelings of enmity, hatred, ill-will or hostility between different racial or religious groups," the government said in a statement.

Only Singapore citizens will be allowed to speak, and they must use one of Singapore's four official languages -- Malay, Mandarin (and related dialects), Tamil and English.

The use of microphones and musical instruments is banned.

A public entertainment licence, a requirement when the speakers' corner was first mooted, has been waived but "Singapore laws will still be in operation," the statement said.

Home Minister Wong Kan Seng has warned speakers to "abide by the laws of Singapore, including the Sedition Act, The Maintenance of Religious Harmony Act and the Penal Code."

The idea of a speakers' corner in tightly controlled Singapore has already been dismissed by the opposition Singapore Democratic Party (SDP) as a "farce."

SDP secretary general Chee Soon Juan, who has twice been jailed for speaking in public without an official permit, said if the government feels it can allow people to speak freely at Hong Lim Park, which borders the financial district, "it will also feel it can ban it anytime."

Chee said outlawing the use of microphones and loud speakers also meant "serious speakers cannot communicate effectively with the masses."

Political scientist James Gomez, who has written a book on the self-censoring nature of Singaporeans, said the ban on audio devices would diminish the size of the audience a speaker could reach.

Although a licence is not required, speakers must register in advance and specify the day they will speak. A daily list of speakers will be posted at the registration centre.

The speakers corner will open on September 1, with registrations opening 10 days earlier.