LONDON (AP) -- Google escalated a feud with Microsoft over cloud computing on Wednesday with a European Union antitrust complaint accusing its tech rival of anticompetitive practices.

In a blog post, Google alleged that Microsoft's licensing practices lock business customers into using its Azure cloud computing platform.

It said Microsoft is the only cloud provider that uses such tactics, which stifles competition, costs businesses more and exposes them to bigger security risks.

Google, which competes against Microsoft with its Google Cloud services, said it filed a formal complaint with the European Commission, the 27-nation bloc's executive branch and top antitrust enforcer.

Microsoft said that it already amicably settled similar concerns raised by European cloud providers, "even after Google hoped they would keep litigating."

Those providers, part of the trade group Cloud Infrastructure Services Providers in Europe, said in July that they withdrew their own complaint after signing a deal with Microsoft.

"Having failed to persuade European companies, we expect Google similarly will fail to persuade the European Commission," Microsoft said in a prepared statement.

A commission spokesperson said it has received the complaint and will assess it "under our standard procedures."

Google said Microsoft changed its licensing terms in 2019 to impose "extreme financial penalties" on businesses that want to use Windows Server software on rival services like Google Cloud and Amazon Web Services. That's despite there being no technical barriers to switch services.

Locking in users to a single technology platform brings heightened security risks, Google said, pointing to a global tech outage in July stemming from a faulty software update by cybersecurity company CrowdStrike that grounded flights and knocked banks and hospital systems offline.