Speaking on Friday (21 May), the Prime Minister said there was 'nothing in the data' to suggest the country is going to have to deviate from the roadmap. He also added that he didn't see any prospect of Covid-status certification - more commonly known as 'vaccine passports' - being introduced on 21 June to go into restaurants or pubs.
The final stage of the Government's plan would see the removal of all legal limits on social contact, and allow for the reopening of night-time economy businesses such as nightclubs, which have primarily been forced to remain shut since the beginning of the first national lockdown in March last year.
Restrictions on large events and live performances would also be expected to end on the same date.
Johnson said: "We will be letting everybody know exactly what sort of arrangements to expect for 21 June.
"But what I can tell you, and just to stress that I am still seeing nothing in the data that leads me to think that we're going to have to deviate from the roadmap - obviously we must remain cautious but I'm seeing nothing that makes me think we have to deviate.
"But on 21 June and vaccine certification - or Covid-status certification I should say - people should bear in mind that I don't see any prospect of certificates to go into pubs or anything else."
Earlier this month, Johnson threw doubt on the further lifting of restrictions by telling a Downing Street press briefing that the Indian Covid-19 variant could 'pose serious disruption' to the Government's plan to drop legal limits on mixing.
However, in a meeting with the 1922 Committee of Tory MPs last week, the Prime Minister said eliminating the 'one-metre plus' social distancing rule was the 'single biggest difference' the Government could bring about in order to get Britain's pubs back into action, and he was confident about abolishing the rule next month.