The mother of murdered teenager Brianna Ghey has called for the government to stop children having access to social media apps on smartphones.

Speaking for the first time since the killers' sentencing, Esther Ghey called the internet the "Wild West".

She told Sunday with Laura Kuenssberg it was "just not doable" for parents to check what children were seeing online.

Scarlett Jenkinson, who killed Brianna, had watched videos of violence and torture on the dark web.

Jenkinson plotted the murder with Eddie Ratcliffe using messaging apps.

Ms Ghey, who is launching a petition to demand the changes, also wants companies to flag searches of inappropriate material, like the videos Jenkinson saw, to parents.

She said: "We'd like a law introduced so that there are mobile phones that are only suitable for under-16s.

"So if you're over 16, you can have an adult phone, but then under the age of 16, you can have a children's phone, which will not have all of the social media apps that are out there now. And also to have software that is automatically downloaded on the parents' phone which links to the children's phone, that can highlight key words.

"So if a child is searching the kind of words that Scarlett and Eddie were searching, it will then flag up on the parent's phone."

During the interview, she said she believed "without a doubt" that Brianna would not have been killed if such safeguards were already in place, adding that "they wouldn't have been searching that in the first place. And if they did search it then the parents would know and to be able to get them some kind of help."

Ms Ghey also said that she had struggled to monitor what Brianna was consuming online - and that she had accessed pro-anorexia and self-harm material.

She said her daughter was "very protective over a phone - it was the cause of a lot of arguments. I can imagine that in most households, this will be the case too. If she couldn't have accessed the sites, she wouldn't have suffered as much."

She told the BBC it was very powerful watching Mark Zuckerberg being confronted by bereaved American parents at a fiery hearing in the US Senate and said "greed needs to be taken out of the picture".

"I think that the focus is always on making such a lot of money, and not really how we protect people or how we can necessarily benefit society," she said.

Watch: Zuckerberg apologises to victims of online exploitation