The law would require social media sites like Facebook to carry warnings on posts the government deems false and remove comments against "public interest".

The move came two days after Facebook founder Mark Zuckerberg said governments should play a more active role in regulating the online platform.

But Simon Milner, who works on Facebook's public policy in Asia, said after the law was tabled, the firm was "concerned with aspects of the law that grant broad powers to the Singapore executive branch to compel us to remove content they deem to be false and proactively push a government notification to users".

"As the most far-reaching legislation of its kind to date, this level of overreach poses significant risks to freedom of expression and speech, and could have severe ramifications both in Singapore and around the world," said Jeff Paine, managing director of the Asia Internet Coalition, an industry association of internet and technology companies in the region.

Speaking to reporters on Monday, Singapore's Law Minister K. Shanmugam said the new legislation would not hinder free speech.

"This legislation deals with false statements of facts. It doesn't deal with opinions, it doesn't deal with viewpoints. You can have whatever viewpoints however reasonable or unreasonable," he said.

Tech giants Facebook, Twitter and Google all have their Asia headquarters in the city-state, a low-tax finance hub seen as a island of stability in the middle of the fast-growing but often-turbulent Southeast Asia region.

Malicious actors

Singapore, which has been run by the same political party since independence from Britain more than 50 years ago, says it is vulnerable to fake news because of its position as a global financial hub, its mixed ethnic and religious population and widespread internet access.

It is ranked 151 among 180 countries rated in the World Press Freedom Index of Reporters Without Borders, a non-government group that promotes freedom of information, below the likes of Russia and Myanmar.

The new bill proposes that the government get online platforms to publish warnings or "corrections" alongside posts carrying false information, without removing them.

This would be the "primary response" to counter falsehoods online, the Law Ministry said.

"That way, in a sense, people can read whatever they want and make up their minds. That is our preference," Law Minister K. Shanmugam told reporters on Monday.

Under the proposals, which must be approved by parliament, criminal sanctions including hefty fines and jail terms will be imposed if the falsehoods are spread by "malicious actors" who "undermine society", the ministry said, without elaborating.

It added that it would cut off an online site's "ability to profit", without shutting it down, if the site had published three falsehoods that were "against the public interest" over the previous six months.

It did not say how it would block a site's profit streams.

The bill came amid talk of a possible general election this year. Law Minister Shanmugam declined to comment when asked if the new legislation was related to a vote.

"This draft law will be a disaster for human rights, particularly freedom of expression and media freedom," said Phil Robertson, deputy director, Asia division, at Human Rights Watch.

"The definitions in the law are broad and poorly defined, leaving maximum regulatory discretion to the government officers skewed to view as "misleading" or "false" the sorts of news that challenge Singapore’s preferred political narratives."