press/push the panic button
From Longman Dictionary of Contemporary Englishpress/push the panic buttonpress/push the panic buttonBritish English to do something quickly without thinking enough about it, because something unexpected or dangerous has suddenly happened → panic buttonExamples from the Corpuspress/push the panic button• And why have governments in the region not pressed the panic button?• Derby County chairman Brian Fearn has refused to push the panic button after Tranmere's 2-1 win.