British media regulator Ofcom Thursday demanded the country's antitrust body to launch an investigation into U.S. tech giants Amazon and Microsoft's dominance of the U.K. cloud market.

Ofcom said its study identified features that make it more difficult for U.K. businesses to switch to and use multiple cloud suppliers.

"The CMA (Competition and Markets Authority) will now conduct an independent investigation to decide whether there is an adverse effect on competition, and if so, whether it should take action or recommend others to take action," Ofcom said.

Reuters on Tuesday reported Ofcom was expected to push for an antitrust investigation into Amazon's and Microsoft's dominance of the U.K. cloud computing market, according to two sources familiar with the matter.

Ofcom, which started looking into cloud services last year, had said in April it was particularly worried about the practices of Amazon Web Services (AWS) and Microsoft because of their market positions and planned to ask the competition regulator to investigate.

United Kingdom businesses have told Ofcom they were concerned about it being too difficult to switch, mix, and match cloud provider, Fergal Farragher, Ofcom's Director responsible for the Market Study.

"So, we’re referring the market to the CMA for further scrutiny to ensure business customers continue to benefit from cloud services," Farragher added.

The communications regulator said its study found that Amazon Web Services (AWS) and Microsoft had a combined market share of supply by revenue in the U.K. public cloud infrastructure services market of 70% to 80% in 2022.

Google was their closest competitor with a share of 5% to 10%, Ofcom added.