Covid: We do need to improve test and trace, admits PM

England's NHS test and trace system needs to improve to provide faster results, Boris Johnson has admitted.

Speaking at a news briefing, he said "I share people's frustrations" at the turnaround times for results.

Chief scientific adviser Sir Patrick Vallance added that there was room for improvement.

Figures have shown that just 15.1% of people who were tested received their result within 24 hours.