UK advisers call for action to stem Covid-19

Patrick Vallance and Chris Whitty, the government's most senior advisers on the pandemic, said infections were doubling every seven days. They said if the rate of infection carried on at the current rate there would be 50,000 cases a day by mid-October resulting in more than 200 deaths a day a month later.

Vallance and Whitty said though the rate of infection varied across the country cases were rising everywhere. One of the most important steps will be to limit contact between households, they said.

The virus is spreading as the UK moves into winter months that make the spread of respiratory diseases easier, Whitty said. This means Britain faces six months of increased threat.

Whitty, England's chief medical officer, said: "This is not someone else's problem; it's all our problem … The seasons are against us."

In a joint briefing with no questions the advisers said the government would have to act to reduce the infection rate while trying to support the economy. They said this would be a difficult balance to achieve.

"If we do too little this virus will go out of control," Whitty said.

After reopening the economy from June following more than two months of lockdown the government is reluctant to shut down the economy again. Health Secretary Matt Hancock is due to update the House of Commons later on Tuesday. He said on Tuesday morning the government had not finalised its plans after working on them over the weekend.

The FTSE 100 index fell 3.3% to 5,813 at 12:00 BST led by British Airways owner IAG. The more UK-focused FTSE 250 fell 4% to 16,865. Shopping centre operator Hammerson, pub group Mitchells & Butlers and transport companies FirstGroup and National Express were among the biggest fallers.

The government has been criticised for inconsistent messaging that has contributed to people becoming less careful about interacting. Johnson said he wanted "bustle" to return to towns and cities and the government branded the reopening of pubs as "independence day". Chancellor Rishi Sunak's "eat out to help out" meal subsidy has been linked with the rising rate of infections.