A powerful group of British broadcasters signed a letter in the Sunday Telegraph calling for tighter regulation of online content.

They specifically called for "independent oversight" in the form of a watchdog.

Tech companies have come under heavy fire recently for how they regulate the content on their platforms.

Traditional TV is under major threat as young people spend more time with Snapchat or YouTube than they do with linear programming.

A group of top British broadcasters have signed a letter calling for more regulation of tech giants like Twitter, Google, and Facebook.

The letter was published in the Sunday Telegraph and signed by the heads of the BBC, Sky, ITV, Channel 4, BT, and Talk Talk. They called for "independent oversight" in the form of a watchdog for tech companies that publish news.

"We do not think it is realistic or appropriate to expect internet and social media companies to make all the judgment calls about what content is and is not acceptable, without any independent oversight," the letter said.

"There is an urgent need for independent scrutiny of the decisions taken, and greater transparency. This is not about censoring the internet, it is about making the most popular internet platforms safer, by ensuring there is accountability and transparency over the decisions these private companies are already taking."

The signees said they saw coming government proposals on internet safety as a "golden opportunity" to address their concerns.

Big tech companies have come under heavy fire recently for misfires in the way they filter content. In July an undercover investigation by Channel 4 revealed that Facebook moderators in Dublin were being trained not to remove some images of child abuse and racist memes from the platform. Last week, the social network was criticized for deleting a post showing nude, emaciated Holocaust victims.

At the same time, traditional TV is under considerable threat from tech firms. A 2017 Ofcom report found that YouTube was the most recognized content brand for viewers ages 12 to 15. And only last week, Facebook released its video-on-demand service, Watch, globally.

Business Insider has contacted Facebook, Google, and Twitter to ask for their response to the letter.