Australia's internet safety watchdog on Thursday threatened to fine Twitter for failing to tackle online abuse, saying Elon Musk's takeover had coincided with a spike in "toxicity and hate."

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 700,000 Australian dollars ($475,000) for every day it missed the deadline.

Since Musk bought the platform in October 2022, he has cut more than 80% of the global workforce, including many of the content moderators responsible for stamping out abuse.

"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 targeting marginalized communities."

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 last year, expressing fears that deep staff cuts would leave the company unable to comply with Australian laws.

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