The spike comes with England set to fully lift restrictions on Monday.
More than 51,000 daily COVID-19 cases were recorded in the UK, authorities announced on Friday, a level not seen since mid-January.
A total of 51,870 new infections were reported, according to official figures — the highest daily tally since January 15.
Nearly 278,000 COVID-19 have been recorded over the past seven days, a 34.9% increase over the previous seven-day period. The number of hospitalisations and deaths have also soared, respectively by 43.4% and 57.4% but remain far below those seen during in the winter and early spring.
The 49 deaths observed over the 24 hours to Friday afternoon bring the UK's COVID-19 death toll to 152,856.
The UK is to lift the last few COVID-19 restrictions on Monday.
The Office for National Statistics estimated in figures released earlier in the day that one in 90 people in England had COVID-19 in the week ending July 10 — rates not seen since February.
Scotland had an even higher rate with one in 90 people believed to have been infected with COVID-19 in that week, while Northern Ireland and Wales had rates of one in 290 and one in 360 respectively.
Meanwhile, Public Health England said in its latest weekly updates on variants, that the Delta variant — which originated in India — accounts for approximately 99% of cases sequenced in the UK.
Dr Jenny Harries, chief executive of the UK Health Security Agency said in a statement that "cases rates are still high and rising, but it is encouraging that the increase in cases does not appear to be associated with a similar increase in hospitalisations and deaths".
"This is testament to the continued success of the vaccination programme in reducing the incidence of severe disease," she added.
More than two-thirds of British adults have been fully vaccinated.
The last few restrictions still in place in England are to be lifted on Monday after the easing was postponed by three weeks. The government has however urged people to use remain cautious with Prime Minister Boris Johnson stressing last week that "this pandemic is not over".