This is the first investigation under the DMA, which took effect on March 7 and was designed to stop Big Tech companies from cornering digital markets.

The commission said in a press release that it "suspects that the measures put in place by these gatekeepers fall short of effective compliance with their obligations under the DMA." It is looking into whether Google and Apple are fully complying with the DMA's rules requiring tech companies to allow app developers to direct users to offers available outside their app stores.

The commission said it is concerned the two companies are imposing "various restrictions and limitations", including charging fees that prevent apps from freely promoting offers. The commission is also investigating whether Apple is doing enough to allow iPhone users to easily change web browsers.

So far the tech firms have made no response.