The UK government has faced criticism over sudden changes in its instructions to hospital workers after telling staff they will have to wear face masks from June 15 onwards. A head of the country’s National Health Service has poured scorn on the government over the changes to the advice issued late on Friday, which has left hospitals scrambling to work out how they will adapt to requirements. Speaking at a daily coronavirus briefing, Health Secretary Matt Hancock said all hospital staff in England a would be required to wear a surgical mask from mid-June onwards while visitors and outpatients have been told to wear some kind of face covering. In response, Chris Hopson, chief executive of NHS Providers, accused the government of making last-minute decisions on political grounds and keeping the health service in the dark. "I think it's the latest in a long line of announcements that have had a major impact on the way the NHS operates, in which those frontline organisations feel they have been left completely in the dark and they are then expected to make significant and complex operational changes either immediately or with very little notice," Mr Hopson told the BBC. Earlier, in a tweet, the NHS boss wrote: “How, as a Government, do you really irritate NHS trust CEOs at the end of another difficult, busy, hard, week? “Announce two major operational policy changes on visiting and PPE usage at 1700 on a Friday afternoon without any notice or consultation. They are not amused” At the same time, the British Medical Association has warned there was "little detail" on how the policy would be implemented, where the masks would come from or how outpatients and visitors would be given them. The sudden requirements on masks have reignited debates in the UK over poor provision of personal protective equipment at the start of the pandemic. "It is absolutely crucial that the government ensures there are enough supplies of face masks for staff, and adequate provision of face coverings for outpatients and the public by June 15," the medical association’s BMA's consultants committee chair Dr Rob Harwood said. British Prime Minister Boris Johnson’s government has faced mounting scrutiny over its handling of the coronavirus outbreak, with the country’s death toll passing the grim milestone of 40,000 fatalities this week. On Friday, the WHO said it is now advising that in areas where the virus is spreading, people should wear fabric masks when social distancing is not possible, such as on public transport and in shops.