The heads of multiple encrypted chat apps, including WhatsApp and Signal, wrote a letter to the U.K. government claiming the proposed Online Safety Bill would “in effect outlaw end-to-end encryption,” the Guardian reports. In the letter, executives wrote, “the bill poses an unprecedented threat to the privacy, safety and security of every U.K. citizen and the people with whom they communicate around the world, while emboldening hostile governments who may seek to draft copycat laws.” Previously, Head of WhatsApp Will Cathcart said the app would leave the U.K. before complying with a law that weakened E2E encryption.