E-safety commissioner Julie Inman Grant, a former Twitter employee, said the platform was now responsible for one in three complaints about online hate speech reported in Australia.

Inman Grant said Twitter had 28 days to show it was serious about tackling the problem or face fines of A$700,000 (US$475,000) for every day it missed the deadline.

She said Twitter must come back with a series of concrete steps showing “what it is doing to prevent online hate on its platform and enforce its own rules”.

“We need accountability from these platforms and action to protect their users,” she said, AFP reports.

“And you cannot have accountability without transparency, and that’s what legal notices like this one are designed to achieve.”

The demand comes as Australia approaches a referendum this year on whether to recognize indigenous people in the constitution, prompting an increasingly intense debate about race.

Indigenous journalist Stan Grant, one of Australia’s most respected media personalities, said in May that he had lodged a complaint with Twitter about the “relentless racial filth” he had copped while using the platform.

Specialist broadcaster National Indigenous Television also said it was taking a break from Twitter due to “the racism and hate that we experience every day on this platform”, it tweeted last month, as quoted by Reuters.

Inman Grant said her letter called for Twitter to explain its impact assessments when reinstating banned accounts, how it engaged with communities who were subject to online hate, and how it was enforcing its own policies that banned hateful conduct.

Since Musk bought Twitter in October 2022, he has slashed more than 80 percent of the platform’s global workforce, including many of the content moderators responsible for stamping out abuse.

In November, Musk declared a broad amnesty that allowed tens of thousands of suspended or banned accounts to rejoin the platform.

“Twitter appears to have dropped the ball on tackling hate,” said Inman Grant, who worked on cyber safety at the company after 17 years at Microsoft.

She said the watchdog was “far from being alone in its concern about increasing levels of toxicity and hate on Twitter, particularly [those] targeting marginalized communities”.

“We are also concerned by numerous reports of content remaining widely accessible that is likely in breach of Twitter’s own terms of service.”

Australia has spearheaded the global drive to regulate social media platforms, and it is not the first time that Inman Grant has publicly singled out Twitter.

She wrote to Musk in November, expressing fears that deep staff cuts would leave the company unable to meet Australian laws.

Major music publishers in the United States launched a legal suit targeting Twitter this month, arguing that the platform had failed to stop “rampant” copyright infringement.

And a European Union commissioner, also in June, accused Twitter of choosing “confrontation” after it pulled out of a voluntary digital code of practice.