Irish musician Jim Corr is taking legal action against Twitter for suspending his account.
The step was taken for an alleged violation of the social media company's policy on "Covid-19 misleading information".
But the guitarist and member of chart-topping band The Corrs claims the move was an unlawful breach of freedom of speech.
His lawyers are now seeking an injunction at the High Court in Belfast to have his account reinstated.
Mr Corr said: "I am challenging Twitter over the suspension of my account with almost 50,000 followers.
"Twitter is acting in conjunction with the Irish government who admitted working with social media companies in order to shut down and stifle certain voices with certain views in a blatant and unacceptable attack on free speech."
The firm suspended his account last December for the alleged violation of its rules.
Mr Corr vehemently denies breaching any regulations and contends that the step has damaged his reputation.
Belfast firm KRW Law wrote to Twitter last month, claiming censorship and requesting an immediate reinstatement.
Lawyers representing the company responded by insisting that it's actions were lawful.
"Your client violated the Covid-19 Misleading Information Policy on multiple occasions, and this policy makes it explicitly clear that an accumulation of multiple violations will result in suspension," correspondence on behalf of Twitter stated.
Denying that any defamatory action had been taken, the letter said reasons for the step were not published.
It also confirmed that legal proceedings will be contested.
With the dispute now set to go to court, KRW Law solicitor Colin McMenamin claimed: "For the Twitter account of Jim Corr to have been suspended demonstrates, again, the unregulated power a social media platform such as Twitter has in both violating the data rights protection of individuals, causing damage to individual reputations and, significantly, determining the scope of individual speech."