Boris Johnson is reportedly set to unveil a five-stage coronavirus alert system when he sets out his "road map" to easing lockdown measures today.
The new warning system, similar to that used for terror threat levels, will be operated by a new "joint biosecurity centre", the agency PA reports.
It is understood that local increases in infection rates will be monitored, with restrictions in England changed in the event of any spikes in the number of people falling victim to the deadly bug.
Alert levels will range from green for level one to red for level five.
When he addresses the nation later today, the Prime Minister is expected to say that the UK is close to moving from four to three.
He is also due to outline his plans to gradually ease the lockdown while telling the country to "stay alert, control the virus and save lives".
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The televised speech will mark a shift from the government's "stay home" slogan as it seeks to move to a new normality, as Covid-19 infections in the UK pass their peak.
Mr Johnson is planning to tell workers who cannot do their jobs from home to begin returning to their workplaces, following social-distancing rules.
The address will be aired at 7pm and will follow a Cobra meeting with Cabinet ministers, leaders of the devolved nations and London Mayor Sadiq Khan.
On Monday, the Government will publish a 50-page document outlining the full plan to cautiously re-start the economy to MPs.
The PM is also expected to warn that the UK is about to enter the most dangerous phase of the coronavirus pandemic, as the country seeks to gradually return to normality while avoiding a second wave of deadly infections.
Mr Johnson will reportedly urge “maximum caution” when he unveils his road map out of the lockdown, saying that the risks are now greater than at any other stage of the crisis.
The UK's death toll now stands at 31,000, after a further 346 deaths were reported yesterday.
