YouTube fans now need to switch off their ad blockers if they want to keep watching free videos on the platform. The popular video-sharing service says it has 'launched a global effort' to get users watching more ads. This includes automatic warning messages that block video playback for ad-block users.

Viewers are reportedly receiving pop-ups telling them that 'video playback is blocked unless YouTube is allowlisted or the ad blocker is disabled'.

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This is accompanied by a prompt instructing users to either 'Allow YouTube ads' or sign up for a YouTube Premium subscription, which costs £12 per month in the UK.

YouTube viewers are being subjected to more and more unskippable ads

According to The Verge, the video prompts can be skipped by some users, but in other cases will fully block videos for anyone with an ad block installed.

The strict new measures follow an announcement by YouTube in June that it would be disabling videos for users with ad blockers.

YouTube claims that using ad blockers violates its terms of service, with spokesperson Christopher Lawton telling The Verge: "ads support a diverse ecosystem of creators globally and allow billions to access their favourite content on YouTube."

The platform has introduced more and more unskippable adverts this year, including during videos on its TV app.

Hundreds of YouTube users have already complained about the change over on a YouTube fan subreddit. One user said: "Finally started getting the 'playback will be disabled' pop ups. Disabled my ad blockers. First ad? Three minute ad (of two) ...for a three minute video."

Another said they won't be signing up for YouTube Premium, stating: "I certainly won't start paying for something that was free for almost 20 years. I might allow ads if they are kept to a strict minimum and preroll only. The way they are pushed now makes the platform unusable for me."

Speaking to Forbes, a YouTube spokesperson said: “The use of ad blockers violate YouTube’s Terms of Service. We’ve launched a global effort to urge viewers with ad blockers enabled to allow ads on YouTube or try YouTube Premium for an ad free experience. Ads support a diverse ecosystem of creators globally and allow billions to access their favorite content on YouTube.”