Explained in plain English

What is 'egregious and reckless'?

When the UK called the alleged drone attack 'egregious and reckless', it meant the act was shockingly bad and showed a dangerous disregard for consequences. This strong language signals the UK's condemnation and its view that Russia's actions are unacceptable. Such diplomatic phrasing is used to convey serious disapproval and to justify a firm response.