What phase of lockdown is the UK in - what does phase 3 entail?

The UK is slowly easing its way out of coronavirus lockdown restrictions, with some non-essential shops and services having re-opened this week while some primary school years returned to the classroom. Under the new rule, people in England can also meet outdoors in groups of up to six, provided social distancing measures are maintained – while other non-essential retail is preparing to re-open from 15 June. The measures are being introduced in a phased easing of lockdown – but what phase are we in now and when will we move on to the next one?troUK/