Adds details throughout, comment request to X in paragraph 6

By Sam Tabahriti

LONDON, July 2 (Reuters) - Britain's culture minister Lisa Nandy said on Thursday she had decided to leave Elon Musk's social media platform X, becoming one of the most senior members of Prime Minister Keir Starmer's government to quit the platform as scrutiny of it intensifies.

"I've decided to leave this platform and my department will too," Nandy said in a post on X, formerly Twitter.

"A platform originally designed for free speech and expression now favours abuse and misinformation over meaningful debate. It isn't healthy for our democracy or our communities and I don't want to support it," she added.

Nandy's Department for Culture, Media and Sport will also stop using the platform.

Nandy appears to be the first elected member of Starmer's cabinet to leave the platform. Attorney General Richard Hermer, who attends cabinet meetings and sits in the House of Lords, withdrew his office from X last month.

X did not immediately respond to a request for comment.

REGULATORY PRESSURE MOUNTS

Nandy's departure from X comes as Musk's platform faces growing regulatory and political pressure in Britain and elsewhere over online safety, misinformation and AI-generated content.

Britain's media regulator Ofcom in January opened an investigation into X over concerns that its Grok AI chatbot was being used to create and share illegal non-consensual intimate images, including content involving minors.

Prime Minister Keir Starmer described some of the images as "disgusting" and "unlawful", while ministers said platforms had a duty to protect users from harmful content.

In mid-January Musk's AI venture xAI said it restricted image editing in Grok, and blocked users from generating images of people in revealing clothing in "jurisdictions where it's illegal."

In early February, Reuters found that even after new curbs, Grok continued to generate sexualised images of people even when users explicitly warned that the subjects did not consent.

In June, British lawmaker Jess Asato sued xAI, alleging Grok had been used to create fake sexualised images of her.

Musk has repeatedly criticised Britain's approach to online regulation, arguing that measures including the Online Safety Act — one of the world's most stringent regimes — risk restricting free speech.