The Prime Minister maintained his cautiously optimistic tone when quizzed about whether the country will proceed to the next step of lifting coronavirus restrictions on June 21.
He said the data was “ambiguous” and urged people to remain “cautious” because infection rates are increasing.
It comes after Nicola Sturgeon delayed the easing of coronavirus measures for many parts of Scotland, announcing that the vast majority of the central belt will remain in their Level 2 restrictions.
Last week the Mr Johnson said he could see nothing in the data to indicate that the next stage of unlocking could not happen on June 21.
Pressed on whether he still felt the same, the PM replied: “I can see nothing in the data at the moment that means we can’t go ahead with step four of the reopening on June 21.
“But we’ve got to be so cautious because there’s no question, the ONS [Office for National Statistics] data of infection rates is showing an increase, we always knew that was going to happen.
“Don’t forget, we always said that the unlocking steps that we’ve taken would lead to increases in infection.
“What we need to work out is to what extent the vaccination programme has protected enough of us, particularly the elderly and vulnerable, against a new surge, and there I’m afraid the data is still ambiguous.”
He said every day they were spending long sessions “interrogating” all the data and looking at various models.
“The best the scientists can say at the moment in their guidance to us is that we just need to give it a little bit longer,” he added.
“I’m sorry that’s frustrating for people. I know that people want a clear answer about the way ahead for June 21. But at the moment, we’ve just got to wait a little bit longer.”
Hopes rose earlier this week that restrictions will be finally lifted on June 21 after the UK reported no deaths from Covid, for the first time in 10 months.
Hailing the “significant milestone”, Health Secretary Matt Hancock told the Standard: “At every step of the way over the past six months our amazing NHS staff have worked day and night, hand in hand with volunteers and our armed forces.
“Everyone in London has pulled together through this pandemic — we haven’t beaten this virus yet so when you get the call, get the jab.”