Professor Chris Whitty and Sir Patrick Vallance are due to address the UK this morning on the fight against coronavirus.
The talk by the chief medical officer and chief scientific adviser is expected to be a stark warning about the sharp rise in cases in recent days.
Daily infections have numbered in the thousands in recent weeks, and further national and regional restrictions to curb the spread are a possibility.
Here's what you need to know about Chris Whitty and Patrick Vallance's address today.
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What is it about?
Coronavirus cases are spiking in the UK and Prof Whitty is expected to warn viewers that the UK has reached a "critical point" in its battle against the virus.
He and Sir Patrick will tell a televised briefing that the country faces a “very challenging winter”, as he lays the ground for tough new restrictions.
The pair will set out potential scenarios that could unfold as winter approaches.
They will also draw on data from other countries, such as Spain and France, which are experiencing a second spike in infections, to underline how their experience could be replicated in the UK.
The chief medical officer is expected to say: “The trend in the UK is heading in the wrong direction and we are at a critical point in the pandemic.
“We are looking at the data to see how to manage the spread of the virus ahead of a very challenging winter period.”
Will Boris Johnson be speaking?
No. It is believed that the address by the two top advisers will lay the groundwork for possible new restrictions, which ministers could announce as soon as Tuesday.
Prime Minister Boris Johnson has reportedly spent the weekend with senior ministers and advisers discussing what action to take as a surge in new infections sweeps the country.
Health Secretary Matt Hancock has refused to rule out a second national lockdown in England if people fail to follow the social distancing rules.
When will they speak?
The pair will address the nation at 11am on Monday.
Where can I watch it?
You can watch it on news channels like the BBC, ITV and Sky.
You can also follow along on the Standard's live blog here.