Girls Aloud star Nicola Roberts refused a request from the government to endorse its Online Safety Bill due to concerns over "loopholes" in the legislation.
The 35-year-old claimed she had been asked to back the bill following a meeting with the Department of Culture, Media and Sport (DCMS) due to her own experiences of abuse and harassment.
However, the singer said the bill wouldn't stop abusive internet users from creating another account with a different name following a ban.
"I am unconcerned with chasing the rabbit. I would rather just fill the hole," she said in a statement on Twitter prompted by the abuse faced by England football team's Black players following their defeat at the Euro 2020 final.
Watch: Girls Aloud's Nicola Roberts hits out at government's Online Safety Bill after racist abuse of England players
"I explained that I couldn't support the bill until something more concrete was developed in tackling that problem. It would be unproductive and a slap in the face for me to support something that ultimately was still contributing to countless people experiencing abuse.
"The online racism we have seen since last night's England game targeted at, in particular, a 19-year-old is despicable.
“While my conversation with the department was private, today highlights why the bill really needs more work.
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"Regardless of whether an abuser's account is blocked or taken down, perpetrators make the time to start another and start again. It highlights why those loopholes need to be filled and this has to stop!"
A DCMS spokesperson said: “This legislation will tackle anonymous abuse. We will not impose a blanket ban on anonymity online because for some groups such as people exploring their sexuality or suffering from domestic abuse it is important.
“However, all social media companies will have to meet their duty of care, which will mean stopping repeat offenders from opening new accounts and working with the authorities to make it easier to find people who set up accounts anonymously to abuse others.”
In 2017, Roberts's ex-boyfriend Carl Davies was given a 15-month suspended prison sentence after he admitted to stalking her.
He sent her thousands of messages between 2012 and 2017 over Instagram and Twitter, including some described as "violent and threatening" in court.
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