Singapore's "fake news" law came into force on Wednesday.
The country's communications and information minister, S. Iswaran, told CNBC the bill is aimed at "enabling" free speech — not "controlling" it.
The legislation, officially known as the Protection from Online Falsehoods and Manipulation Bill, was passed earlier this year.
The goal, Iswaran told CNBC's Nancy Hungerford on Wednesday, is to ensure that the internet "fosters accurate information" that people can rely on to make "appropriate judgment calls and decisions."
"This is a global commons, and we need to make sure that in this global commons, we foster trust and confidence that what we see and what we hear is reliable, is trustworthy, and we can use that to make informed decisions," Iswaran said.
In a statement to CNBC late Wednesday in Asia, a Facebook spokesperson said: "As the new law comes into effect, we hope the government's assurances that it will not impact free expression will lead to a measured and transparent approach to its implementation."
Before the bill was put before parliament at the beginning of April, Facebook said it shared the Singapore government's commitment to reducing the spread of online falsehoods. It also said it was "concerned" that aspects of the law could "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."
U.S.-based social media companies are under increasing scrutiny by governments outside the United States, especially in Europe. Singapore's law appears to go further than anything on the books in the European Union, however.
The minister said tech companies had "asked for regulation," as it was in their "collective interest."
"We've been working very closely with them because, in order for this legislation to work, there need to be technical solutions, and we've had very constructive and productive conversations with them," he said.
Asked who should decide if a piece of content is reliable, Iswaran said: "No solution is perfect."
"If we say tech companies should decide, there are obvious drawbacks to that. If we say that governments decide, there will also be comments on that," he said. "And if you say it's the judiciary, there are also issues."
As a result, he said, the government has decided to let its executive arm "make the call in the first instance" while allowing it to be subject to a review by the judiciary.
"If there's a disagreement, it can be taken to the courts, and a decision will be made at the courts," Iswaran said.
— CNBC's Ted Kemp contributed to this report.