Liverpool City Region will remain in Tier 2 for now, but Public Health Director Matt Ashton said the direction of the numbers is worrying.
Having brought its infection rate down from more than 700 cases per 100,000 people in October to under 100 earlier this month, recent days have seen the level shoot up again. The weekly infection rate for the city for the 7 days up to December 20 is now 169.5, with a total of 844 cases recorded - a rise of 348 cases from the previous week.
Mr Ashton said a big concern is that there has been a recent increase in cases amongst those aged 80 and over - a group that are particularly vulnerable to the worst impacts of the virus.
Speaking exclusively to the Liverpool Echo in a live session on our Facebook page today, Mr Ashton said: "It's worrying that we are now seeing these increases, we did a remarkable job in bringing the levels down here and were the only area of the country to exit the national lockdown in a lower tier than before it.
"We managed to sustain the lower rate - under 100 cases per 100,000- after the lockdown for around 14 days.
"Unfortunately, since then the rate has gone up and it continues to rise.
"It is across all age groups, but there are particular increases in the over 80s age group, which we know will result in further pressure on our health system.
"And the direction of travel is only going one way, unfortunately the rates will continue to increase."
Another concern for Liverpool and other cities is what is going on down south.
London and large parts of the South East have been placed into a new Tier 4 level of restrictions after it was found that a new, more infectious variant of Covid-19 was spreading in those areas.
Mr Ashton said it is highly likely that the mutant strain is already in Liverpool.
He said: "When we look at what is going on in the rest of the country and the significant pressure that London and the South East are currently under - it feels very much like we are heading in that direction.
He added: "Unfortunately it looks like Tier 2 isn't strong enough to stop the rates of infection going up again and that might be for a multitude of reasons - including the new mutated strain of the virus."