The father of a teenage girl who died in Britain after viewing harmful online content on Monday criticised the response of social media companies to a report aimed at preventing future tragedies.

Londoner Ian Russell, the father of 14-year-old Molly, described their reaction as  "underwhelming and unsurprising", demonstrating "business as usual" approach.

Regulation, such as the British government's proposed Online Safety Bill, was the only way to end the "inertia" shown by social media sites towards safety, he added.

The inquest into her death heard that of the 16,300 posts Molly saved, shared or liked on Instagram in the six-month period before her death, 2,100 related to depression, self-harm or suicide.

Coroner Andrew Walker, who led the inquest, subsequently wrote to Meta, Pinterest, Twitter and Snapchat in September last year.

In a "prevention of future deaths" report sent to the social media firms and the UK government, Walker urged a review of the algorithms used by the sites to provide content.

Russell expressed disappointment at their feedback and the fact that Instagram's parent company Meta had not shown any "significant change in direction".

"One perhaps would have hoped that looking at the level of detail that was presented to the coroner...," he told the PA news agency.

"It would have focused minds and compelled tech platforms to react more positively to put safety higher up their agenda," he added.

"But that doesn't seem to be the case, particularly in Meta's case."

- Tougher action -

In his inquest into Molly Russell's death, Walker ruled that she had died from an act of self-harm while suffering from the "negative effects of online content".

It would not be "safe" to conclude it was suicide, he said.

Her death in November 2017 led her family to set up a campaign highlighting the dangers of social media.

The Online Safety Bill is due to be debated by MPs on Tuesday.

In its current form, it would require tech companies to remove illegal material from their platforms, with a particular emphasis on protecting children from seeing harmful content. It would also impose heavy fines for sites that break the rules.

Dozens of MPs with the ruling Conservatives however have put their name to an amendment demanding tougher action.

The rebels MPs want the owners of social media platforms to face jail time if they fail to protect children from seeing damaging content.

After the inquest into his daughter's death, Russell said it was "time the toxic corporate culture at the heart of the world's biggest social media platform changed.

A senior Meta executive had said the content that the platform's algorithms had pushed to his daughter was safe, said Russell.

"If this demented trail of life-sucking content was safe, my daughter Molly would probably still be alive -- and instead of being a bereaved family of four, there would be five of us looking forward to a life full of purpose and promise that lay ahead for our adorable Molly," he added.