A lawyer representing the online message board 4chan says it won’t pay a proposed fine by the UK’s media regulator as it enforces the Online Safety Act.

According to Preston Byrne, managing partner of law firm Byrne & Storm, Ofcom has provisionally decided to impose a £20,000 fine “with daily penalties thereafter” for as long as the site fails to comply with its request.

“Ofcom’s notices create no legal obligations in the United States,” he told the BBC, adding he believed the regulator’s investigation was part of an “illegal campaign of harassment” against US tech firms.

Ofcom has declined to comment while its investigation continues.

“4chan has broken no laws in the United States - my client will not pay any penalty,” Mr Byrne said.

Ofcom began investigating 4chan over whether it was complying with its obligations under the UK’s Online Safety Act.

Then in August, it said it had issued 4chan with “a provisional notice of contravention” for failing to comply with two requests for information.

Ofcom said its investigation would examine whether the message board was complying with the act, including requirements to protect its users from illegal content.

4chan has often been at the heart of online controversies in its 22 years, including misogynistic campaigns and conspiracy theories.

Users are anonymous, which can often lead to extreme content being posted.