Keyword blocking is used to stop online ads appearing next to news articles containing specific terms, and there is concern in the media industry that excessive use of the practice in relation to coronavirus is damaging the ability of publishers to monetise vital journalism.

Reach has developed a tool that uses IBM Watson’s natural language processing to determine whether news content is ‘safe’ for brands to advertise next to.

Using the technology means ads will only appear alongside Covid-19 related news stories deemed to be neutral or positive, including articles about homeschooling, cooking tips or how to stay fit at home. The categorisation of stories will be determined by the IBM Watson AI system.

The companies estimate that the tool could make available around 70% of news content currently being blocked across national and regional newsbrands.

Benjamin Pheloung, general manager for Mantis, said: “There’s no reason why a brand shouldn’t want to have an advert placed next to a positive story, like one about sports and media personality Gary Lineker donating two months wages to the Red Cross to help fight Covid-19.”

Tim Dutton, client executive for media and entertainment, IBM UK and Ireland, said: “Safeguarding an organisation’s brand is essential to maintaining consumer trust during this unprecedented time.”

Earlier this month, the culture secretary urged companies not to block ads from appearing next to virus-related news during the pandemic. Trade body Newsworks estimated that the loss to news brands could total £50m if the pandemic lasts for three months.