Boris Johnson announced on Tuesday that pubs, restaurants, hotels and hairdressers could reopen from July 4, providing they are COVID-secure. Other businesses where people are in close contact, including gyms, pools, spas and tattoo parlors have to stay shut for now.
He said that local measures could also be put into place for any regional flare-ups, but he also confirmed that the easing of restrictions would be under constant review.
Britain has one of the highest death tolls in the world from Covid-19, but the number of cases has been steadily falling.
The head of the Confederation of Business Leaders (CBI), Carolyn Fairbairn, said government guidance would be "critical for success".
Theatres and concert halls can reopen but not for live performances.
Most global travel remains out of reach, but the government gave the green light to staycations with the reopening of hotels and campsites.
Detailed guidance to allow these organisations to reopen safely is also expected to be published and is thought to contain measures such as one-way systems, pre-booked tickets and increased ventilation. One meter is the minimum distance recommended by the World Health Organization. Current rules only allow groups of up to six people to meet outside.
"The problem with cricket as everybody understands, is that the ball is a natural vector of disease, potentially, at any rate and we've been round it many times with our scientific friends", said Johnson.
However, Johnson was keen to point out that the measures can be reversed if the coronavirus appears to return.
McClarkin urged the devolved governments in Scotland, Wales and Northern Ireland to follow suit.
Some scientists are anxious that the government is reopening the economy too fast and that a track-and-trace system meant to quickly stamp out any outbreaks is not fully functional.
"Given the significant fall in the prevalence of the virus, we can change the two metres distancing rule from the 4th July", adding this rule was particularly challenging for the hospitality industry.
"If that does not happen, we will go back to a situation where transmission starts to rise again", he said.
But he said the virus has not gone away and the Government "will not hesitate to apply the brakes and re-introduce restrictions - even at national level - if required".
"To come out of it too early is extremely risky", he said.