Washington: US Federal Reserve Chair Jerome Powell has raised “serious concern” over Facebook’s upcoming digital coin ‘Libra’. Testifying before the House Financial Services Committee, Powell raised serious objections on Facebook cryptocurrency slated to arrive in 2020, the Wired reported on Wednesday. Under Facebook subsidiary Calibra, the social networking giant has planned to introduce a digital wallet for Libra. The wallet will be available on Messenger, WhatsApp and as a standalone app and is expected to be launched in 2020. (IANS)