Images of self-harm and suicide on social media like those viewed by teenager Molly Russell “normalise” such behaviour and leave people at risk, the suicide prevention minister has said.

Jackie Doyle-Price warned that such content now posed an online threat as great as child grooming.

“Many of you in this room will have been moved by the story of Molly Russell which was recently in the news. I’m very grateful to her father Ian for his courage in sharing her story and I’ve viewed the material that Molly accessed using her Instagram account,” she said in a speech to the National Suicide Prevention Alliance (NSPA) conference.

“I have no doubt that the suicide and self-harm content of the kind that Molly viewed had the effect of normalising self-harm.

“In normalising it, it has an effect akin to grooming. We have embraced the liberal nature of social media platforms, but we need to protect ourselves and our children from the harm which can be caused by both content and behaviour.”

Ms Doyle-Price, who confirmed she was due to meet Facebook later on Tuesday to discuss the issue, said the government was prepared to introduce regulation if social media did not act.

“We must look at the impact of harmful suicide and self-harm content online. I am hugely encouraged that the government’s forthcoming White Paper to address online harms will consider what more can be done to address this harmful content online.

“If companies cannot behave responsibly and protect their users, we will legislate. Providers ought to want to do this. They shouldn’t wait for government to tell them what to do. It says a lot about the values of companies if they do not take action voluntarily.”

NSPA co-chair Brian Dow said some social media companies have “dragged their heels” on the issue.

Ms Doyle-Price called on internet companies to “step up to their responsibilities” when it came to protecting users.

The family of Molly, 14, found she had viewed content on social media linked to anxiety, depression, self-harm and suicide before taking her own life in November 2017.

Later on Tuesday, digital minister Margot James is expected to announce new government policy that could force social media firms to remove illegal content and sign a code of conduct protecting vulnerable users.

Health secretary Matt Hancock is also due to meet Instagram officials on Thursday to understand how it is tackling harmful online content.