Boris Johnson's mandatory mask policy has riled the Tory old guard | Katy Balls

An edict seen by some as un-Conservative is exposing divisions over the prime minister's cautious approach to the pandemic

In the fortnight before the UK went into lockdown, Boris Johnson appeared in a video chat with Dr Jenny Harries to answer a series of questions about coronavirus. The deputy chief medical officer went over the regular symptoms, the low risk of large gatherings and the cons of face masks for all. She told a nodding prime minister that masks should only be worn if a medical professional tells you to, otherwise you could contaminate the mask and transfer the virus: It's really not a good idea and it doesn't help."

Fast forward four months and that advice - along with several other parts of their conversation - has gone out of the window. The government has announced that face coverings will soon become compulsory in shops and supermarkets. Following in the footsteps of Scotland, and after a weekend of mixed messages from ministers, the new rule will come into effect on Friday 24 July, with a 100 fine for anyone caught not wearing one.