Britain's competition watchdog announced today that it would investigate Microsoft's $16 billion acquisition of Nuance Communications, a company specializing in artificial intelligence and speech technologies.

The Competition and Markets Authority (CMA), which has been tightening its regulatory oversight of Big Tech, said it was examining whether the purchase will result in less competition in the UK market.

Microsoft said in April that it would acquire Nuance to bolster its cloud services for healthcare.

The transaction has previously been approved by regulators in the United States and Australia, with no conditions attached.

According to Reuters, the deal, which will be Microsoft's second-largest acquisition after the $26.2 billion acquisition of LinkedIn in 2016, is expected to receive unconditional EU antitrust approval.

According to the sources, Microsoft has also held preliminary discussions with the CMA ahead of submitting a formal request for clearance of the Nuance purchase.

The CMA said interested parties had until January 10 to submit comments on the arrangement.