BRUSSELS, Sept 25 (Reuters) - Alphabet (GOOGL.O) unit Google filed a complaint to the European Commission on Wednesday against what it said were Microsoft's (MSFT.O) anti-competitive practices to lock customers into Microsoft's cloud platform Azure.

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.

Google opened up a fresh legal squabble with Microsoft Corp. over the lucrative cloud market, after it filed a complaint to the European Union’s antitrust watchdog alleging abusive conduct by the firm.