OpenAI picked Microsoft Bing as the default search engine for its premium ChatGPT Plus service, deepening ties with a company which has become a key investor over the past four years.

Yusuf Mehdi, head of consumer marketing with Microsoft, explained in a blog the latest collaboration will speed delivery of search results and improve their provenance.

“Now, ChatGPT answers can be grounded by search and web data and include citations so you can learn more”.

While the move is initally open to paying ChatGPT users, OpenAI plans to extend access to those employing the free version through a plug-in.

Mehdi stated developers could submit plug-ins for business and consumer services including Microsoft’s various “copilot” offerings, alongside its search engine and ChatGPT.

Microsoft deployed an upgraded version of ChatGPT on its Bing search engine in February.

It faces competition from Google in terms of employing AI in search.