Britain’s competition regulator on Tuesday said that it is investigating to see if Google parent Alphabet’s partnership with artificial intelligence startup Anthropic has resulted in reduced competition.

The Competition and Markets Authority (CMA) said it is looking into whether a partnership between the two firms has led to a “relevant merger situation,” and if that “may be expected to result in a substantial lessening of competition” in the U.K.

The regulator has invited comments from interested parties before beginning a formal investigation.

Alphabet and Anthropic were not immediately available for comment when contacted by CNBC.

Google agreed to invest up to $2 billion in Anthropic back in October, in a move that involved a $500 million upfront cash injection and an additional $1.5 billion to be poured in over time. This was on top of prior investments Google had made in the company, which has reportedly given it around a 10% stake in the AI startup.

Anthropic is the developer of Claude, a rival chatbot to OpenAI’s ChatGPT.

U.S. giants have been aggressively investing in companies they think can lead in artificial intelligence, amid a global frenzy around the technology.

Anthropic is one of those companies. Amazon, for example, last year pledged to invest up to $4 billion in Anthropic.

However, regulators in the U.S. and U.K. have become increasingly concerned by the investments being made by technology giants in smaller firms.

The CMA in April said it was opening an investigation into partnerships between Microsoft and French AI firm Mistral, and into the relationship between Amazon and Anthropic, as well as into Microsoft’s hiring of former employees from Inflection AI.

– CNBC’s Hayden Field and Ryan Brown contributed to this report.

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