Coronavirus is not under control in much of the US, according to a report from scientists at Imperial College London, who warn that relaxing the lockdowns further now could result in another surge in deaths.

Around half of all states still have reproduction rates above one, the report warns, meaning that each coronavirus patient is infecting more than one other. Any reproduction rate above one means the virus spreads exponentially.

The findings come as almost every state and territory in the US has begun to ease restrictions on movement, despite many not having hit the milestones set by the US Centers for Disease Control and Prevention for doing so. Robert Redfield, the head of the US Centers for Disease Control and Prevention, told the Financial Times this week that he expected a second wave of cases this winter.