Singapore plans to decriminalize oral and anal sex for adult heterosexuals under legislation unveiled Thursday, but the government said sex between homosexuals will remain banned.

The government posted proposed amendments to the city-state's Penal Code -- the result of a three-year review -- on a Web site, and Singaporeans have a month to offer feedback. The Ministry of Home Affairs will consider the input before presenting the proposals to Parliament early next year.

The amendments that have generated the most water-cooler buzz in strait-laced Singapore are those that would legalize oral and anal sex between consenting heterosexuals over age 16 -- and the retention of the law against acts between homosexuals.

That drew immediate criticism from People Like Us, a gay rights group.

"If the government aims for an open, inclusive society, it should be doing all it can to overturn prejudice and discrimination, rather than give people reason to remain close-minded through retaining (the ban) for symbolic purposes," the group said in a statement.

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The Home Affairs Ministry said it wants to modernize the laws "to be in line with social mores and emerging societal trends" -- but that doesn't include homosexuality.

"Singapore remains, by and large, a conservative society. Many do not tolerate homosexuality," said a note published with the amendments.

However, it said it would continue its policy of not proactively prosecuting private homosexual acts.

"Gross indecency" between two men can lead to two years in jail, but it's rarely punished. Singapore has a thriving gay community.

Other proposed amendments would ban necrophilia, toughen penalties for sex with minors under 14, and introduce penalties for men who rape their wives.

The amendments would also expand the Sedition Act to cover "the wounding of racial feelings," and would toughen credit card fraud laws.

A change in the "unlawful assembly" law would broaden its focus to groups "whose common object is to commit any offense, and not just those relating to public tranquility."

Outdoor gatherings of more than four people now require a police permit -- a law seen by critics as an attempt to curb political dialogue.

Such laws were highlighted in September, when protesters were confined to an indoor lobby during annual International Monetary Fund and World Bank meetings held in Singapore.