The government has raised the alert level to four with immediate effect - signalling that coronavirus transmission is 'high or rising exponentially'.
In a statement to the House of Commons, health and social care secretary Matt Hancock repeated his recent warning that the UK was 'at a tipping point' in the pandemic.
Following a warning from the UK CMO and the government's chief scientific adviser that the epidemic is now doubling every seven days - putting the UK on track for 50,000 cases a day by mid October - the health secretary highlighted a WHO warning that new cases in Europe were now higher than levels seen at the start of the pandemic in March.
New restrictions to slow the spread of the virus now appear inevitable across the UK. Ahead of a statement due on 22 September from prime minister Boris Johnson, the Northern Ireland executive has already announced an extension of COVID-19 restrictions that will mean households can no longer mix indoors in most cases and that no more than six people can meet in a garden.
Following problems with access to COVID-19 testing after a surge in demand in recent weeks - problems the government has admitted could take 'weeks' to resolve - Mr Hancock has said essential workers including GPs will be prioritised for tests.
The decision to prioritise GPs comes despite a warning from the BMA's GP committee that the government should not resort to 'robbing Peter to pay Paul' by testing one group at the expense of another.
Government guidance says employers 'can refer essential workers for testing if they are self-isolating because either they or member(s) of their household have coronavirus symptoms'.
It adds: 'They can do this by uploading the names and contact details of self-isolating essential workers to the secure employer referral portal.'
Essential workers then receive a 'a text message with a unique invitation code to book a test for themselves (if symptomatic) or their symptomatic household member(s) at a regional testing site', the guidance says. Employers need to register to use the booking system.
Mr Hancock told parliament that the government was currently discussing new measures to slow the spread of COVID-19, warning: 'There is no doubt this virus is accelerating.'
Along with priority access to testing for essential workers, the health secretary highlighted a £500 payment for low-income workers who were forced to self-isolate, along with fines rising to £10,000 for people who refuse to self isolate.
He told MPs: 'We need to prioritise the tests for those who need them most to save lives, protect the most vulnerable and to make sure our health services, businesses and schools can operate safely.
'We have today published a list of where tests are being prioritised. First to support acute clinical care, second to support and protect people in care homes, third NHS staff inc GPs and pharmacists, fourth targeted testing for outbreak mgmt and surveillance studies, fifth testing for teaching staff with symptoms.'
The health secretary added: 'The system relies on people coming forward for tests if and only if they have symptoms or have been specifically advised to by a health professional.'