Meta will train its generative artificial intelligence (AI) models with its European users' public content and conversations with the Meta AI chatbot, the firm said Monday. 

The decision represents a major volte-face from the Facebook and Instagram owner, which has previously appeared wary of the European Union's stringent regulations on the use of personal data. 

People based in the EU who use Meta platforms can opt out of having their data used for training purposes, the social networking giant said.

The changes would not apply to the accounts of users under 18, nor to private messages of users to family and friends, the tech giant said on social media. 

WhatsApp messenger will for the time being not be affected by the changes. 

When Meta AI first launched in the EU, the tech giant was at pains to point out that the chatbot was not trained on data from European users.

Its rollout on the continent was delayed by more than year as a result of overlapping European regulations on emerging technologies, including the General Data Protection Regulation (GDPR), AI and digital markets.

Developing "large language models" (LLMs) like Meta AI requires vast reserves of data, which is heavily regulated in the European Union where it relates to individual users.

AI is an overriding priority for Meta as for other Silicon Valley giants.

The group plans to invest $60-65 billion this year, with much of the cash going into data centres, servers and network infrastructure necessary to develop AI models.