Google and Apple hold a “vice-like” grip over how people use mobile phones, stripping any meaningful choice from the system and potentially hiking costs, Britain’s competition regulator said on Tuesday.

The Competition and Markets Authority (CMA) said it had provisionally found that the two groups were able to leverage their market power to create largely self-contained ecosystems, Reuters reported from London.

The statement is a fresh warning to tech groups after the regulator, with British government backing, stepped up scrutiny of the power they wield in a world increasingly lived online.

It recently told Facebook owner Meta it had to sell Giphy, the popular animated images platform it bought in 2020.

The regulator said on Tuesday it would consult on its initial Apple and Google findings and would welcome responses by February 7, 2022. It expects to issue a final report by June.

“Apple and Google have developed a vice-like grip over how we use mobile phones and we’re concerned that it’s causing millions of people across the UK to lose out,” CMA Chief Executive Andrea Coscelli said.

Chris Philp, the tech and digital economy minister, said Britain’s “new pro-competition regime” would level the playing field between tech giants and smaller businesses.

Apple says its ecosystems provide security and privacy, enabling businesses to sell goods and create jobs. “Apple believes in thriving and dynamic markets where innovation can flourish,” it said.

Google said Android provided people with more choice than any other mobile platform in deciding which apps and app stores they use.

It said its ecosystem supported almost a quarter of a million jobs in Britain, and as a result of recent changes, 99 percent of developers qualified for a service fee of 15 percent or less.

“We’re committed to building thriving, open platforms that empower consumers and help developers succeed,” it said.

The CMA’s report set out a range of options , including making it easier for users to switch between Apple’s iOS and Google’s Android phones without losing functionality or data.