Boris Johnson is facing a furious backlash from members of his Conservative party as he prepares to put the final lifting of coronavirus lockdown restrictions in England on hold.
The Prime Minister is expected to announce the ending of social-distancing rules, which had been slated for 21 June, will be delayed for four weeks to 19 July.
The move follows warnings from scientists that the rapid spread of the Delta variant first identified in India risks a "substantial" third wave if it is allowed to spread unchecked.
Mr Johnson is expected to appeal to the public to show patience, with one last push to ensure that when controls do finally end it is "irreversible".