Microsoft faces a dispute in the U.K. over how it charges customers who buy cloud software services that rival its own Azure, the latest antitrust challenge to the U.S. tech giant’s approach to licensing.

Microsoft is in the crosshairs of a U.K. competition class-action style lawsuit that's seeking £1 billion (around $1.25 billion at current exchange rates)

The probe was approved by FTC Chair Lina Khan ahead of her likely departure in January. The election of Donald Trump as U.S. president and the expectation he will appoint a fellow Republican with a softer approach toward business, leaves the outcome of the investigation up in the air.

Microsoft faces legal action in Britain over a claim that thousands of businesses using cloud computing services provided by Amazon, Google and Alibaba could be paying higher licence fees to use Windows Server software.

The FTC has launched an antitrust investigation into Microsoft, according to multiple reports — corroborating earlier reporting by the Financial Times.